The periodic motion of the Earth's spin axis in space (nutation) is dominantly forced by external torques exerted by the Moon, Sun and planets. On the other hand, long-periodic geophysical forces (with periods longer than several days), mostly caused by the changes in the atmosphere and oceans, have dominant effects in polar motion (in terrestrial frame) and Earth's speed of rotation. However, even relatively small short-periodic (near-diurnal) motions of the atmosphere and oceans can also have a non-negligible influence on nutation, thanks to the resonance that is due to the existence of a flattened outer fluid core. The retrograde period, corresponding to this resonance, is roughly equal to 430 days in non-rotating quasi-inertial celestial reference frame, or 23h 53min (mean solar time) in the terrestrial frame rota ting with the Earth. The aim of the present study is to use the geophysical excitations in the vicinity of this resonance to estimate their influence on nutation, based on recent models of atmospheric and oceanic motions. To this end, we use the numerical integration of Brzezinski's broad-band Liouville equations and compare the results with VLBI observa tions. Our study shows that the atmospheric plus oceanic effects (both matter and motion terms) are capable of exciting free core nutation; both its amplitude and phase are compatible with the observed motion. Annual and semi-annual geophysical contributions of nutation are of the order of 100 microarcseconds. They are slightly different for different at mospheric/oceanic models used, and they also differ from the values observed by VLBI - the differences exceed several times their formal uncertainties., Jan Vondrák and Cyril Ron., and Obsahuje bibliografické odkazy
In the paper a problem of elaboration and the use local quasige oid on mining areas in south-eastern Poland is discussed. The models were elaborated within research projects carried by Institution of Geodesy and Cartography AGH in years 1996-2005 and related to mining caused terrain surface deformation problems. One part of the carried research was elaboration of quasi-geoid model that can be used in practical aspects of mine surveying. There is an example of this quasi-geoid model application in leveling surveys presented in the paper. Furthermore, discussed quasi-geoid models elaborated for small areas provide detailed information about the shape of this surface and they determine database completing existing country models as for example Leveling Geoid 2001 for area of Poland., Piotr Banasik., and Obsahuje bibliografické odkazy
The structural changes of interfacial transition zone of two concrete systems reinforced by polypropylene/polyethylene and basalt fibers were studied by Raman microspectroscopy. The interfacial transition zone was found in the 0-20 μm in vicinity of quartz/feldspar aggregate surface. The calcium carbonate, ettringite and alite and belite bands were used for determination of interfacional transition zone size by Raman spectroscopy. Similar behaviour has been shown the cement matrix in neighbourhood of PP/PE fibers. There is not observed any concentration gradient of cement hydration product in the vicinity of 1 μm diameter basalt fiber., Vladimír Machovič, František Kolář, Petr P. Procházka, Šárka Pešková and Pavel Kuklík., and Obsahuje bibliografii
This paper presents a real-time cycle slip detection and repair strategy for the BDS-3 triplefrequency and quad-frequency phase observations. For the triple-frequency phase observations, two EWL code-phase combinations and one GF-phase combination are jointly employed to detect and repair cycle slips. Based on the different performances in the success of cycle slip detection and repair, this paper uses GF-phase combinations to detect and repair cycle slip individually. Specifically, the GF-phase combination with a large MTIV value is applied to detect cycle slip possessing the stronger ability to resist ionospheric delay. Besides, the GF-phase combination with a higher success rate of cycle slip repair is selected to repair cycle slip, and the classic LAMBDA method and Ratio test are implemented to fix the cycle slip solution and evaluate reliability separately. For the quad-frequency phase observations, we employ a supernumerary EWL combination based on the triple-frequency, which can directly determine the cycle slip value of the 4th frequency. The results show that the cycle slip estimation value still can detect and repair all real and artificially added cycle slips even under harsh conditions. Moreover, the overall cycle slip repair success rate is greater than 99.99 %., Hao Wang, Shuguo Pan, Wang Gao, Fei Ye, Chun Ma, Ju Tao and Yunfeng Wang., and Obsahuje bibliografii
Micro-displacement monitoring in Slopy a nd Zbojnícka caves is described. It st arted at the end of 2005 with the use o f verified, stable and sensitive 3D crack gauges TM71 produced by GESTRA Sedloňov. Two gauges were installed in the caves across significant tectonic structures. Registered displacements are pertinent to the last significant earthquake events. The f irst one appeared in March 13, 2006 at Vrbové, M=3.2; and later in August 5-8, 2006, a swarm of 10 quakes M max = 2.2 at Trstín was registered. The results indicated trends of dextral strike-slip displacements across observed fault structures in both of those caves., Miloš Briestenský and Josef Stemberk., and Obsahuje bibliografické odkazy
The paper is focused to the analysis of permanent and epoch-wise GPS networks extending over the region of Slovakia. We considered almost all available GPS data measured in Slovakia and its close surroundings over the period of last 17 years. Our analysis is based on combination of homogenized permanent and epoch-wise network solutions leading to the ITRF2005 related coordinates, velocities and their global covariance matrix. Estimated velocities were further reduced for APKIM2005d plate motion model and submitted to the velocity filtering and smoothing using the least square collocation approach. The obtained homogenized intra-plate velocity field is then used for the surface deformation analysis. The final and partial results of this procedure are discussed in order to extend information about recent regional geo-kinematics of Slovakia., Ján Hefty, Linda Hipmanová, Ľubomíra Gerhátová, Miroslava Igondová and Branislav Droščák., and Obsahuje bibliografii
The paper presents results of epoch satellite GPS and gravimetric measurements performed on the geodynamic network in central part of the Stołowe Mts. between 1993 and 2009. The research results show significant changes of gravity on most of the points and significant horizontal movement of one point in the central part of the area. The results confirm present day activity of the zone where faults Polický, Bělský and Czerwona Woda Fault Zone exists. In addition, they correspond with the studies of seismic activity in this part of the Sudety Mts., Stefan Cacoń, Jan Kapłon, Bernard Kontny, Josef Weigel, Otakar Švábenský and Jiři Kopecký., and Obsahuje bibliografii
The combination method of results of different space geodetic techniques was recently improved and used to process approximately eight-year data obtained by three space geodetic techniques. The results are compared with the results obtained by the old approach of this method and finally with the solutions of ITRF 2005., Vojtěch Štefka., and Obsahuje bibliografii
Distributed control and measurement system for evaluation of hydrologic, geomechanical and other parameters has been built up in the medieval ore mine Jeroným. The instrumentation is generally based on commercial measurement and control kit and sensors. Technique of implementation of special sensors, e.g. laser distance meter and/or CCBM probe for measurement of rock massif stress changes, is also described. The distributed system is integrated into the existing seis mic recording station equipped by data transmission via GSM network. Comprehensive monitoring system is modular in order to have possibility to change the system configuration., Jaromír Knejzlík and Zdeněk Rambouský., and Obsahuje bibliografické odkazy
Three year monitoring of micro-displacements on four tectonic fracture planes in a tunnel driven by a milling cutter into granitoids of Bohemian Massif revealed micro-movements that develop in certain trends and impulses. Two investigated fractures are of the Krušné Hory Mts. orientation (NE - SW), other two of Sudeten orientation (NW - SE). These have been found the two prevailing fracture orientations in the massif. Results from all the four fractures indicate trends in overfaulting of southern blocks over the northern ones and a stress state model characteristic of approximate N-S compression with overthrust vergence to N. Besides, some impulses were indicated with abrupt occurrence that dominates the development of movements. The first most significant impulse occurred by the end of the year 2004, the second one at the break of 2005/6. The coincidence of the impulses with earthquake events is discussed., Josef Stemberk and Blahoslav Košťák., and Obsahuje bibliografii