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222. Global and regional seasonal variations of the geoid detected by grace
- Creator:
- Jan Kostelecký, Aleš Bezděk, and Jaroslav Klokočník
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, GRACE mission, seasonal variations, eoid, 7, and 551
- Language:
- English
- Description:
- Since 2002, the US-German GRACE (Gravity Recovery and Climate Experiment) mission has been providing a precise survey of the Earth's time-variable gravity field, with unprecedented temporal and spatial sampling. GRACE time-variable gravity fields provide a means of measuring the temporal and spatial variations of mass redistribution within the Earth system. The GRACE mission has started a new era in studying a series of geophysical problems ranging from deep Earth structure to tracking mass redistribution on and near the surface of the Earth. Time variability of the gravity field presented here is based on the transformation of “monthly gravity field models” to the geoid. We show the changes caused by the global water cycle and land hydrology., Jan Kostelecký, Aleš Bezděk and Jaroslav Klokočník., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
223. GNSS reference solution for permanent station stability monitoring and geodynamical investigations: the ASG-EUPOS case study
- Creator:
- Szafranek, Karolina, Bogusz, Janusz, and Figurski, Mariusz
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, GNSS stations monitoring, reference frame, ASG-EUPOS, 7, and 551
- Language:
- English
- Description:
- a1_The aim of this paper is to present the strategy of determination of the reference solution for the ASG-EUPOS (Active Geodetic Network - European Position Determination System) coordinate monitoring system. ASG-EUPOS is a network of permanent GNSS (Global Navigation Satellite System) stations controlled by the Polish Head Office of Geodesy and Cartography (HOGC), which main role is to realize the ETRS89 (European Terrestrial Reference System) in the territory of Poland. The Centre of Applied Geomatics (CAG) of the Military University of Technology (MUT) performs a control processing of the network and it is the leader of the ASG+ (the supporting modules for ASG-EUPOS system real-time services) project within which the coordinate monitoring system was developed. The coordinate monitoring is aimed to assess the actual performance of the GNSS stations and the reliability of the system and its services. The Polish realization of the ETRS89 is also controlled, where the deviation of the actual coordinates from the reference values are monitored. Furthermore, the monitoring enables the analysis of factors that degrade the individual GNSS stations and assess the solution stability which has impact on the quality of the determined geodynamic parameters. The reference solutions (coordinates and their changes over time) were determined according to the recommendations of the IAG sub-commission for the European Reference Frame concerning densification of EUREF. The paper presents the determination of the reference cumulative solution and the results of the processing of a few years long series of GNSS observations. The analysis are performed by the Bernese 5.0 and CATREF software. The results consists of daily and subdaily ASG-EUPOS reference solutions. They are also considered as input data for geodynamic studies to determine the horizontal and vertical velocity fields., a2_Estimation of the individual station velocities is of crucial importance for the ETRF (European Terrestrial Reference Frame) reference frame maintenance to assess the compatibility of the current station position with its catalogue (reference) value and apply coordinate correction if necessary., Karolina Szafranek, Janusz Bogusz and Mariusz Figurski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
224. GPS/BDS triple-frequency cycle slip detection and repair algorithm based on adaptive detection threshold and FNN-derived ionospheric delay compensation
- Creator:
- Qian, Nijia, Gao, Jingxiang, Li, Zengke, Li, Fangchao, and Pan, Chen
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- GPS sítě, GPS netwoks, BDS, triple-frequency cycle slip detection and repair, geometry-free (GF), ionosphere-free (IF), ionospheric disturbances, adaptive detection threshold, feed-forward neural network (FNN), 7, and 551
- Language:
- English
- Description:
- A refined triple-frequency cycle slip detection and repair algorithm for GPS/BDS undifferenced observables under high ionospheric disturbances is proposed. In this method, three linearindependent optimal observables combinations for GPS/BDS are selected. The residual ionospheric delay estimated from a "calculation-prediction mechanism", namely flexibly determine whether to calculate delay by observables themselves or to predict delay by a feedforward neural network (FNN), is used to compensate for the detection values. Additionally, we devise an adaptive detection threshold based on actual noise level to detect the cycle slip, and adopt the modified least-square decorrelation adjustment (MLAMBDA) to fix integer cycle slip. The performance of the proposed algorithm was tested with observables at 30 s sampling rate in a 2-day geomagnetic storm period. Results showed that the proposed algorithm can detect and repair all kinds of cycle slips as small as one cycle in the case of high ionospheric disturbances. No false repairs are generated despite the occurrence of very few misjudgments., Nijia Qian, Jingxiang Gao, Zengke Li, Fangchao Li and Chen Pan., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
225. Gravity measurements in The Geodynamic Network Sudety
- Creator:
- Lukavec, Petr and Lederer, Martin
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, gravity measurements, gravity network, gravity acceleration, 7, and 551
- Language:
- English
- Description:
- The Geodynamic Network Sudety was joined to the Czech Gravity Reference Network (CGRN) by two weeks of the relative gravity measurements. The gravity stations of the CGRN were used as the anchor stations. There were used two relative gravimeters LaCoste & Romberg G. The method of measurement, used instruments, mathematical processing, variants of result computations and their accuracy are discussed., Petr Lukavec and Martin Lederer., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
226. Gravity measurements in the region of the geodynamic network HIGHLANDS (the Bohemian massif)
- Creator:
- Kujal, Roman, Vladimír Schenk, and Zdeňka Schenková
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, Česká vysočina (pohoří), Bohemian massif, gravity measurement, geodynamic network HIGHLANDS, geodynamic processes, 7, and 551
- Language:
- English
- Description:
- During 2007 and 2008 there were realized gravity measurements using the relative gravimeter Scintrex CG-5 on sites of geodynamic networks HIGHLANDS and fundamental gravity sites of the Czech Gravity Reference Network. The gravity measurements were concentrated on monitoring the long-term trends of gravity acceleration changes among individual measurement sites. The methodology of measurement was optimized and preliminary time changes in gravity differences among sites were determined., Roman Kujal, Vladimír Schenk and Zdeňka Schenková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
227. Groundwater level variations in the seismically active region of Western Bohemia in the years 2005-2010
- Creator:
- Gaždová, Renata, Oldřich Novotný, Málek, Jiří, Valenta, Jan, Brož, Milan, and Kolínský, Petr
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, zemětřesení, seizmicita, earthquake, seismicity, Čechy západní (Česko), Bohemia, Western (Czechia), earthquake swarm, groundwater level, 7, and 551
- Language:
- English
- Description:
- The western part of the Bohemian Massif (Vogtland/West-Bohemia region at the Czech-German border) is characterized by relatively frequent intraplate earthquake swarms and by other manifestations of current geodynamic activity, such as mofettes, mineral and thermal springs. In this study we analyze variations of groundwater level in four hydrological wells in the region during the years 2005-2010. Monitoring during the previous time interval of 2000-2004 is also mentioned and used for comparison. Two of the wells are located in the epicentral region of Nový Kostel, and the other wells are more distant. The time interval includes the 2008 earthquake swarm when all the wells displayed a noticeable drop in the water level. This effect was observed up to epicentral distances of nearly 30 km, which exceeds the distances of hydrological changes observed during previous earthquake swarms. Moreover, it seems that a small rise in the water level preceded the intervals of increased seismic activity, which could represent a certain precursory phenomenon. On the other hand, the hydrological changes in the Nový Kostel area were relatively small, indicating that this epicentral area is not hydrologically linked with the seismically active fault at depth. Consequently, more suitable localities for hydrological monitoring should be sought in a broader vicinity of Nový Kostel., Renata Gaždová, Oldřich Novotný, Jiří Málek, Jan Valenta, Milan Brož and Petr Kolínský., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
228. Henry Morton Stanley: příspěvek k dějinám afrických výzkumů
- Creator:
- Jan Vratislav Želízko
- Publisher:
- nákl. vl.
- Format:
- print and 35 s.
- Type:
- model:monograph and TEXT
- Subject:
- Geografie jako věda. Výzkum. Cestování, Biografie, Stanley, Henry Morton, 1841-1904, cestovatelé, výzkumné expedice, travellers, research expeditions, Afrika, Africa, 910.4-051, 910.4, (73), (092), (0:82-4), (0.036.6), 7, 8, 91, and 929
- Language:
- Czech
- Description:
- napsal J.V. Želízko., KČSN, Název z obálky, Obsahuje bibliografické odkazy, and Separát z: Sborníku České zeměvědné společnosti, roč. 11, 1905
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
229. Historický místopis obce Nové Vsi n. P
- Creator:
- Josef Jan Fučík
- Publisher:
- Vydáno podporou okresní správní komise a j. korporací a péčí Učitelské jednoty Komenský
- Format:
- print, text, regular print, and 166 s. : il. ; 26 cm
- Type:
- text, volume, handbook, studie, soupisy, model:monograph, and TEXT
- Subject:
- Geografie Česka a Slovenska, reálie, cestování, historický místopis, Česko, domy, majitelé domů, pozemkové knihy, dějiny, Nová Ves nad Popelkou (Česko), 913:94, 721, 332.816.2, 930.253:347.235, (437.316), (048.8), 908(437.1)Nová Ves nad Popelkou, 7, and 913(437)
- Language:
- Czech
- Description:
- ze starých a nových knih pozemkových vypsal a sestavil Jos. J. Fučík and Rozložený tit. l.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
230. Historie výkladu statické teorie slapů na Zemi
- Creator:
- Štefl, Vladimír
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- Galilei, Galileo, 1564-1642, Newton, Isaac, 1642-1727, slapové jevy, astronomie, fyzická geografie, Měsíc, Země, gravitace, tides, physical geography, Moon, Earth, gravity, sea water, mořská voda, příliv, odliv, 7, and 551
- Language:
- Czech
- Description:
- Vladimír Štefl. and Rubrika: Historie fyziky
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public