The notion of heat uncompensated transformation has early been introduced by Clausius in 1854 and next, after fifty years of forgetting, in 1904 Duhem has revalorized it and combined it with a new notion of work uncompensated transformation [3]. In this way the so-called ClausiusDuhem inequality has been established. In our paper we wish to present a novelized procedure of estimating the role of the uncompensated transformations of heat and work within the flow of viscous and heat conducting working fluid like water stream. The original procedure was introduced by Puzyrewski and it is essential in expressing of a local, in time and space, balance of entropy. Futhermore, this unique approach leads to redefinition of the efficiency notion, as is usually applied to fluid-flow machineries, to a new one important in computational fluid dynamics (CFD) three-dimensional modeling. As a result, it is shown that usage of the polytropic efficiency, instead of the isentropic efficiency, is more convenient and seems to be natural in CFD approach. Helpfully, we have also found a correlation between those two efficiency definitions with usage of proposed new dimensionless (criterion) number.
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This article describes the establishment of an alpine gravimetric calibration baseline in Poland's Tatra Mountains and the development of a methodology for performing static gravimeter calibration on that baseline. This baseline was established in response to the recent rise in geodynamic research in mountainous areas and the related need to calibrate the gravimetric scale used in such gravimeter research to a high degree of accuracy. The fact that the environmental conditions of such an alpine gravimetric calibration baseline differ considerably from those observed in flat terrains made it necessary to study the impact which rapid changes in atmospheric pressure and environmental temperature may exert on the performance of gravimeters used in such survey. It was also important to study how the method by which the instruments were transported (by automobile, cable car, or on foot) affected their performance. The project led to the establishment of an alpine gravimetric calibration baseline and yielded a set of recommendations for how to proceed with scaling the gravimeters at such a baseline.
PL
Przedstawione prace związane są z założeniem górskiej grawimetrycznej bazy kalibracyjnej w Tatrach oraz opracowaniem metodyki przeprowadzania na niej kalibracji grawimetrów statycznych. Założenie takiej bazy wynika z nasilenia w ostatnich czasach badań geodynamicznych w górach i związaną z tym potrzebą ujednolicenia na wysokim poziomie dokładności skali grawimetrycznej, używanych do tych badań grawimetrów. Z uwagi na znaczące różnice warunków środowiskowych na bazie górskiej w porównaniu z tymi, jakie obserwuje się na bazach zakładanych w terenach płaskich, niezbędne było przeprowadzenie badań wpływu szybkich zmian ciśnienia atmosferycznego i temperatury otoczenia na pracę grawimetrów, które są używane w pracach pomiarowych. Niemniej ważne było zbadanie wpływu wykorzystywanego środka transportu (samochód, kolej linowa, ręczny transport instrumentów) na pracę instrumentów rodzaju. W wyniku przeprowadzonych prac utworzona została górska grawimetryczna baza kalibracyjna oraz podano zalecenia jak należy postępować przy skalowaniu grawimetrów na tej bazie.
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W niniejszym artykule przedstawiono wyniki prac związanych z transformacją współrzędnych geodezyjnych z układu "Borowa Góra" na układ współrzędnych "1942". Zbadano cztery warianty rozwiązania zagadnienia z uwzględnieniem dwóch poziomów dokładności. Wykonano transformację współrzędnych Płaskich X i Y metodą Ryšavego oraz współrzędnych sferycznych B i L metodą Buršy-Wolfa, które są metodami ścisłymi. Zaprezentowano również możliwość dokonania transformacji współrzędnych metodami przybliżonymi: metodą średnich wartości \deltaX i \deltaY dla arkuszy map w skali 1: 1 00 000 oraz metodą strefową. W wyniku przeprowadzonych na wybranym materiale mapowym testów opracowano algorytm i program obliczeniowy, który posłużył do przeliczenia, z dokładnością [...]4.5 m, współrzędnych punktów z układu "Borowa Góra" na układ "1942". Dokonano również porównania, w formie graficznej, wyników uzyskanych przy użyciu ścisłych i przybliżonych metod transformacji.
EN
Studies on transformation of "Borowa Gora" to "1942" coordinate system were undertaken in order to express geological gravimetric data in uniform, presently obligatory coordinate system and in homogeneous gravimetric system. Four variants of solution of this problem were studied, considering two levels of accuracy. First level consists oftwo precise transformation methods: - Ryšavy method, which ensure accuracy of re-calculation of [...] 0.50 m; - Buršy-Wolf method, ensuring accuracy of re-calculation of [...] 0.7 m. Second level comprises approximate methods: - method of mean values, ensuring accuracy of transformation of [...]4.5 m; - zonal method, which ensures accuracy from [...] 5 m to [...] 8 m. It was found in the course of the tests, conducted on the selected maps, that method of mean values, ensuring accuracy of trąnsformation of [...] 4.5 m is the most useful for geological-geophysical documentation. Method of mean values, for which special algorithm and calculation program was prepared at the Institute of Geodesy and Cartography, was applied for transformation from "Borowa Gora" to "1942" coordinate system of about million gravimetric points stored at the geological database.
Analizę oparto na wynikach przeprowadzonych czterech testów: testu na materiale katalogowym, testu na materiale mapowym, testu terenowego oraz testu poprawności odwzorowania profili punktów geologicznych. Celem analizy było określenie faktycznej dokładności określenia współrzędnych dowolnego punktu zawartego w bazie danych grawimetrycznych po jego transformacji z układu "Borowa Góra" na układ "1942". Opisano przeprowadzone testy, a wyniki ich wraz z oceną dokładności przedstawiono w postaci tabelaryczno-graficznej.
EN
Special algorithm and caIculation program prepared at the Institute of Geodesy and Cartography, called BG/42, enabled transformation of coordinates of about million gravimetric points stored at the geological database from "Borowa Gora" to "1942" coordinate system. Formal error of recaIculating with the use of this program is [...]4.5 m. However, real accuracy of point location after transformation is influenced by accuracy of determination of points stored at the gravimetric database. In order to asses real accuracy of transformation of coordinates with the use of the method prepared at IGiK, the following tests were carried out: - on the catalogue data - on the map data - field test of correctness of point location on geological profiles. It results from the conducted tests, that coordinates of points, stored at the geological database in "Borowa Gora" coordinate system are affected with large errors, consisting of errors of mapping based of terrain details and of errors of reading point coordinates from maps. Total error due to these reasons is [...]104 m, while error of transformation method itself of [...]4.5 m is not large, which was documented by field test on geodetic points. Hence real precision of determination of location of gravimetric point stored at the geological database after its transformation from "Borowa Gora" to "1942" coordinate system can re ach [...]105 m. However, for majority of points located on map sheets around central meridians 15o and 21o value of this error does not exceed 100 m, which was confirmed by results of field test.
Założona w latach 1994–1999 nowa podstawowa osnowa grawimetryczna kraju oparta została na 12 punktach absolutnych. Pomiary na tych punktach zostały wykonane pięcioma grawimetrami balistycznymi. Wyniki powtórnych pomiarów, wykonanych na kilku punktach różnymi grawimetrami, wykazały różnice dochodzące do 30 mikrogali. Zaszła zatem konieczność przeprowadzenia weryfikacji tych pomiarów. W tym celu wykonano pomiary względne zespołem czterech grawimetrów Lacoste & Romberg na 25 przęsłach łączących 12 punktów absolutnych. Przeprowadzona analiza umożliwiła zaakceptowanie pomiarów wykonanych tylko trzema grawimetrami – FG 5-101, FG 5-107 i JILAg 5, których wskazania nie różniły się więcej niż 3 mikrogale. Grawimetry te uznano za reprezentujące międzynarodowy standard grawimetryczny i ich wskazania przyjęto jako wzorzec dla polskiej grawimetrycznej osnowy podstawowej.
EN
New basic gravimetric network in Poland was established between 1994 and 1999. It is based on 12 points, so-called absolute points; the measurements on these points were done with five ballistic gravimeters: FG 5-101, FG 5-107, JILAg 5, IMGC and ZZG. Absolute points were selected, according to recommendations of the International Gravimetric Commission, on the lowest floors of such buildings, as observatories, museums, schools, churches, etc. It gives a chance, that the absolute point will survive for at least several decades. The paper includes the detailed descriptions of all absolute points. The measurements were performed by German, American, Finnish, Italian and Polish teams. As results of measurements, done with the use of various gravimeters, differed on a few points even by 30 microgals, it was necessary to make their verification. The direct connecting measurements between absolute points were performed with the use of four LaCoste & Romberg gravimeters. The measurements were done on 25 so-called long spans (160– 300 km). Results of absolute determinations and results of relative connections were jointly analysed. This analysis enabled to eliminate those gravimeters, which do not fulfil the assumed criteria of reliability – IMGC and ZZG. The remaining gravimeters: FG 5-101, FG 5-107 and JILAg 5, which did not differ in readouts more than 3 microgals, were found to be representatives of the international gravimetric standard. Their readouts were assumed as the standard for Polish gravimetric basic network. The results of relative measurements on 685 spans of network were adjusted to 12 absolute points and to 3 points on the territory of Germany. Finally set of values of gravity acceleration for 354 points of network was obtained. This network is homogeneous, as far as gravimetric level and gravimetric scale is concerned; it also fulfils accuracy and construction requirements.
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Przedstawiono opis osnowy oraz szczegóły dotyczące prac pomiarowych na punktach osnowy, które były wykonane w latach 1994-1997.
EN
Basic gravimetric network of Poland was established in sixties, so now it does not fulfil the modern needs of geodesy, especially considering more common recent use of satellite measuring techniques. In 1977 the general project of modernisation of the network was prepared in the Institute of Geodesy and Cartography and approved by the Head Office of Geodesy and Cartography. All new points of the modernised gravimetric network were stabilised by concrete poles between 1978 and 1987, but the measurements were possible only in 1992, when the newest La Coste & Romberg gravimeters were purchased by the Institute of Geodesy and Cartography. Project of gravimetric network, verified by experts from the Geodesy Committee, Polish Academy of Sciences, was approved again by the Department of Surveyor General of Poland in 1993. New gravimetric network comprises fundamental point, located in the Observatory of the Institute of Geodesy and Cartography in Borowa Gora, which was already used several times to measure absolute acceleration of gravity, 16 absolute points (9 of which were already measured), 351 stabilised terrain points and two meridian’s calibration base lines, based on 6 absolute points. The Institute of Geodesy and Cartography started to measure the new network in 1994 and the measuring works were completed finally in 1997. Values of differences in acceleration of gravity Ag were calculated using scales of gravimeters determined on the basis of national gravimetric network, and next were re-calculated in 1997 to the system defined by absolute points. The whole network consists of 674 spans, where 722 measurements of differences in acceleration of gravity [delta]g were performed. It must be emphasised, that 62% of errors of Ag values measured on network spans does not exceed 0.010 mGal, while criterion of correctness is 0.020 mGal.
Praca jest próbą ustosunkowania się do zjawiska dryftu. Na podstawie materiału polowego, jak i dostarczyły pomiary polskiej sieci grawimetrycznej w latach 1994 -1996, przeprowadzono analizę, która wykazuje, że tzw. dryft krótkookresowy ma charakter głównie przypadkowy.
EN
Polish gravimetric network was measured between 1994-1996 with the use o f LaCoste & Romberg relative gravimeters. These instrument is presently recognised as one o f the most precise in the world, but while using it so-called drift phenomenon also appears. Drift is the result o f decreasing the resilience force o f the main measuring system and is manifested by change o f readings in time; it is a function o f inner and outer factors. The aim o f this work was to make the detailed analysis o f drifts, which appear during measurement o f segments o f Polish gravimetric network, as it is commonly known, that proper drift elimination increases compatibility o f gravimetric measurements and hence their accuracy. In the course o f measurements the scheme o f observations: A-В, В-A, A-В was applied; it ensured repeatability o f measurements for points at three consecutive surveys. Pairs o f drifts observed on segments o f gravimetric network were the subject o f analysis. 1500 drifts were analysed in total. The charts and graphs presenting all daily drifts o f gravimeters used for measurements from June 1994 till October 1996 were prepared. As a result o f all analyses it was found, that there is no relation between measured values o f difference in acceleration and values o f drifts, which appear on this segment. No relation was observed between values o f drift and observer, but they were influenced by the way o f transporting gravimeters. Analysis o f drifts confirms the initial assumption, that for particular type o f measurements and for small time differences modelling o f drifts by first-order polynomial is sufficient; this procedure can be even omitted due to random character o f drifts.
W artykule przedstawiono wyniki prac geodezyjno-grawimetrycznych mających na celu powiązanie fundamentalnego punktu absolutnego podstawowej osnowy grawimetrycznej kraju z 8 punktami grawimetrycznymi znajdującymi się na terenie Obserwatorium w Borowej Górze. W przyszłości punkty te będą służyły do wykonywania na nich jednoczesnych porównawczych wyznaczeń absolutnych kilkoma grawimetrami balistycznymi. Wyznaczenia takie mają na celu stałą kontrolę standardów grawimetrów balistycznych stanowiących wzorzec dla systemu IGSN 71.
EN
Fundamental point o f basic gravimetric control network in Poland is located at the Observatory in Borowa Góra. Within last twenty years this point was used several times for determining absolute acceleration o f gravity, utilising various ballistic instruments. Besides fundamental point there are eight gravimetric points with permanent stabilisation within the area o f the Observatory; they can be also used for making absolute measurements. Such an arrangement o f gravimetric points within the Observatory allows for simultaneous, comparative absolute determinations, using several ballistic gravimeters. These determinations are part o f the activity o f the MAG Gravimetric Commission; they serve for permanent check o f gravimetric standards at the IGSN 71 system. In order to perform such works at the Observatory in Borowa Gora, it was necessary to make relative gravimetric measurements between gravimetric points and to determine their heights above sea level, a well as X, Y plane coordinates. Results o f the measurements will be used for making reductions to the absolute determinations, conducted simultaneously with several ballistic gravimeters, so they could be comparable.
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