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1

Basis of geostatistics for scientists specialising in natural sciences based on the example of ordinary kriging

Zarychta R., Zarychta A.

Geoinformatica Polonica

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2014

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T. 13

77--82

EN

The paper presents four stages of acquiring the knowledge about kriging. The second stage has been focused on application of the free software E{Z}-Kriging, which allows to learn the empiric basis of ordinary kriging.

PL

W niniejszym artykule zaprezentowano cztery etapy dochodzenia do wiedzy o krigingu. Drugi etap powiązano z darmową aplikacją E{Z}-Kriging, która pozwala zapoznać się z podstawami empirycznymi krigingu zwyczajnego

2

Zastosowanie krigingu zwyczajnego do rekonstrukcji i wizualizacji reliefu w miejscach odkrywkowej eksploatacji piasku

Zarychta R., Zarychta A.

Archiwum Fotogrametrii, Kartografii i Teledetekcji

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2013

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Vol. Spec.

133--146

PL

W niniejszym artykule zaprezentowano jeden ze sposobów odtwarzania rzeźby (sprzed rozpoczęcia eksploatacji piasku na cele podsadzkowe) czterech pól piaskowych dawnego wyrobiska „Siemonia”. Morfologia analizowanego terenu została zwizualizowana w oparciu o archiwalną mapę geologiczną (arkusz Wojkowice) z zastosowaniem metod geostatystycznych, w tym m.in. krigingu zwyczajnego. Jest to jedna ze znanych technik estymacji (szacowania), nazywana B.L.U.E. (best linear unbiased estimator). Zgodność dopasowania matematycznych modeli sferycznych do wariogramu empirycznego potwierdzono w procedurze kross-walidacji. Uzyskane wartości błędów (błąd średni, błąd średni kwadratowy oraz błąd średni kwadratowy standaryzowany) są w znacznym stopniu zgodne z notowanymi w literaturze naukowej. Wygenerowana rzeźba badanego terenu pod postacią modelu trójwymiarowgo w wyniku przeprowadzonej pełnej analizy geostatystycznej jest dość mocno uwydatniona w porównaniu do modelu otrzymanego bez zastosowania analizy strukturalnej i kross-walidacji.

EN

Extraction of mineral resources, including rocks, usually causes some significant changes of the landscape. Transformation of the relief which character and scale can be analysed by means of cartographic materials seems to be the most interesting. Reconstruction of the relief of the period prior to the exploitation is a starting point for such investigation. It can be done basing on archival cartographic materials which are difficult to obtain. However, too varied morphological material of the area can lead to erroneous conclusions which suggests interpretation of three-dimensional models of the relief. Hence, the paper deals with reconstruction and visualisation of the relief (in the period before the exploitation) of four sand fields of the old sand mine excavation “Siemonia”. A geological map of Poland (Wojkowice sheet) has been used for the purpose. A geostatical analysis by means of the programmes Surfer 8. and ArcGIS 10.1. has been performed on the map. An estimation method called ordinary kriging, which is related to B.L.U.E. (best linear unbiased estimator), where the condition of the lack of weight of the measurement (the sum of weight is equal to 1) is fulfilled, has been applied. The calculated values of errors (mean error, mean squared error and mean squared standardised error) obtained as a result of application of the cross-validation procedure are, to a large extent, in agreement with predetermined values of errors given by numerous authors in the scientific literature. It confirms proper “manual” adjustment of two mathematical models of spherical variograms and empirical variograms. The generated contour map of the investigated area (based on estimated points of sampling in nodes of the interpolation grid) together with its three-dimensional digital model are more adequate (due to significant marking of the relief) to the previous state of the investigated area than the two other presented types of cartographic visualisations made without application of the geostatistical methods. Hence, the graphic presentation of results, mentioned as the last one, can be only applied to visualise the relief without any detailed geomorphological interpretations due to its inaccuracy. It seems to be obvious that detailed analyses can be performed basing on a digital model of the terrain accompanied by its contour map obtained when reconstruction of the relief is made by means of geostatistical methods (especially ordinary kriging).

3

Zastosowanie „korekty efektu wygładzenia” w badaniach form geomorfologicznych

Zarychta A., Zarychta R.

Archiwum Fotogrametrii, Kartografii i Teledetekcji

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2013

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Vol. Spec.

119--132

PL

Intensywne, wręcz rabunkowe wydobycie kruszyw naturalnych – m.in. piasków stosowanych do celów przemysłowych przyczynia się do znaczących zmian w krajobrazie. Na uwagę zasługuje teren województwa łódzkiego – w tym gmina Kobiele Wielkie, w granicach której odnotowano postępującą degradację wydmy parabolicznej na skutek intensywnej eksploatacji czwartorzędowych piasków do celów budowlanych. Rabunkowa działalność gospodarcza człowieka spowodowała, a także nadal powoduje zanik pierwotnego zasięgu i kształtu wspomnianej formy geomorfologicznej. Stąd autorzy niniejszego opracowania za główny cel przyjęli odtworzenie fizjonomii wydmy parabolicznej (sprzed okresu eksploatacji) z wykorzystaniem metod geostatystycznych (w tym krigingu zwyczajnego). Przeprowadzone liczne rekonesanse terenowe miały na celu analizę i ocenę aktualnego stanu formy eolicznej oraz oszacowanie jej dawnego kształtu i zasięgu z wykorzystaniem odbiornika GPS. Z uwagi na uzyskaną niewielką liczbę punktów próbkowania utworzony hipotetyczny trójwymiarowy model badanej wydmy metodą krigingu zwyczajnego – punktowego nie przyniósł zadowalających efektów. Niemniej jednak zastosowanie korekty efektu wygładzenia zaproponowanej w 2005 r. przez J.K. Yamamoto pozwoliło na sporą redukcję powstałego „efektu zafałszowania”. W konsekwencji odtworzony kształt i zasięg analizowanej formy wyraźnie różni się od wyjściowego modelu cyfrowego. Uzyskane wyniki, a w związku z tym idealnie dopasowane wariogramy świadczą o prawidłowo wykonanej analizie geostatystycznej, a tym samym o dużej wiarygodności zbudowanego Numerycznego Modelu Terenu.

EN

Intensive exploitation of natural environment resources, including natural aggregates – among them sand used for industrial purposes e.g. building industry, production of glass or backfilling contributes to significant physiocenotic changes. Concerning the problem, the area of Łódź voivodeship merits attention, especially Kobiele Wielkie commune (Dudki village) where progressive degradation of a parabolic dune occurs. It is caused by excessive extraction of Pleistocene fluvioglacial sand for building purposes. Overexploitation of natural resources has already caused and it is still causing decrease of the primary range and form of the discussed geomorphological form. Therefore, the authors of the paper decided to aim at reconstruction of the physiognomy (of the period prior to extraction) of the dune which had been formed in Dudki village. Geostatistical methods, including ordinary kriging, have been applied for the purpose. The lack of archival cartographic materials of the investigated area made the authors go on numerous field trips which goal was to analyse and estimate the current state of the aeolian form and to determine its shape and range by means of a GPS receiver. A hypothetical three-dimensional model of the investigated dune made by application of an ordinary kriging method has not brought satisfying effects. Too many overestimated and underestimated values of altitude values caused significant generalisations resulting in smoothing of the whole model. Application of the correction of the smoothing effect proposed by J. K. Yamamoto in 2000 enabled considerable reduction of the “falsification effect”. Therefore, the reconstructed shape and range of the dune is considerably different from the one obtained at the initial stage of the investigation by means of the digital model. The obtained results of the correction of the smoothing effect giving in result perfectly matching variograms prove properly performed geostatistical analysis. Hence, despite the lack of cartographic materials showing the state of the dune prior to the extraction (which could have been compared with the obtained results of desktop studies) it has been assumed that the reconstructed model of the dune matches its previous physiognomy and therefore it is the most suitable.

4

Multi objective optimization of wear resistant TiAlN and TiN coatings deposite by PVD techniques

Szparaga Ł., Ratajski J., Zarychta A.

Archives of Materials Science and Engineering

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2011

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Vol. 48, nr 1

33-39

EN

The goal of this paper is to determine, the optimal layer thickness of deposited coatings, in respect of thermal strain and stresses.

5

Mechanical properties of monolayer coatings deposited by PVD techniques

Dobrzański L. A., Lukaszkowicz K., Zarychta A.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

423-426

EN

Purpose: This research was done to investigate the mechanical properties of monolayer coatings (Ti/CrN, Ti/TiAlN, Ti/ZrN, CrN, TiAl/TiAlN, Zr/ZrN, TiN) deposited by PVD technique (reactive magnetron sputtering method) onto the substrate from the CuZn-40Pb2 brass. A thin metallic layer was deposited prior to deposition of ceramic monolithic coatings to improve adhesion. Design/methodology/approach: The microstructure of the coatings was cross section examined using scanning electron microscope. The residual stress was obtained from the parabolic deflection of the samples, after the coating deposition applying Stoney's equation. The microhardness and Young's modulus tests were made on the dynamic ultra-microhardness tester. Tests of the coatings' adhesion to the substrate material were using the scratch test. Findings: Obtained results show that all the coatings are in a state of compressive residual stress. The stiffness of the examined coatings is between 224 - 330 mN/micrometres, while Young's modulus is between 258 - 348 GPa. Concerning the adhesion of the coatings measured by scratch test, it has been stated that the critical load LC2 for coatings, deposited onto the brass ranges from 41 to 57 N. Research limitations/implications: In order to evaluate with more detail the possibility of applying these coatings in products used in the building and power industries, further investigations should be concentrated on the determination of the tribological properties of the coatings. Originality/value: The paper contributes to better understanding and recognition the structure of thin coatings deposited by PVD techniques. It should be stressed that the mechanical properties of the PVD coatings obtained in this work are very encouraging and therefore their application for products manufactured at mass scale is possible in all cases where reliable, very hard and abrasion resistant coatings, deposited onto brass substrate are needed.

6

Mechanical properties of multilayer coatings deposited by PVD techniques onto the brass substrate

Lukaszkowicz K., Dobrzański L. A., Zarychta A., Cunha L.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 15, nr 1-2

47--52

EN

Purpose: This research was done to investigate the mechanical properties of coatings deposited by PVD techniques onto brass substrate. Design/methodology/approach: The coatings were produced by reactive dc magnetron sputtering. The microstructure of the coatings was cross section examined using scanning electron microscope. The residual stress was obtained from the parabolic deflection of the samples, after the coating deposition applying Stoney’s equation. The microhardness and Young’s modulus tests were made on the dynamic ultra-microhardness tester. Tests of the coatings’ adhesion to the substrate material were made using the scratch test. Findings: Obtained results show that all the coatings are in a state of compressive residual stress. The lower values of the internal stresses in multilayer coatings result from the possibility of stress release in the successive alternating layers of the relatively soft titanium. Highest hardness values are obtained in monolayer coatings. The stiffness of the examined coatings is between 195 ÷ 330 mN/μm, while Young’s modulus is between 210 ÷ 348 GPa. Concerning the adhesion of the coatings measured by scratch test, it has been stated that the critical load LC2 for coatings, deposited onto the brass ranges from 40 to 50 N. The greatest critical load has been obtained for monolayer coatings. Research limitations/implications: In order to evaluate with more detail the possibility of applying these coatings in tools, further investigations should be concentrated on the determination of the tribological properties of the coatings. Practical implications: The tools and functional materials coated by the PVD process have shown significant improvement. Good properties of the PVD coatings make these coatings suitable for various technical and industrial applications. Originality/value: It should be stressed that the mechanical properties of the PVD coatings obtained in this work are very encouraging and therefore their application for products manufactured at mass scale is possible in all cases where reliable, very hard and abrasion resistant coatings, deposited onto brass substrate are needed.

7

Struktura i własności przeciwzużyciowych i odpornych na korozję wielowarstwowych powłok naniesionych techniką PVD na podłoże ze stopu miedzi z cynkiem

Dobrzański L., Lukaszkowicz K., Zarychta A.

Ochrona przed Korozją

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2005

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nr 6

204-213

PL

W pracy wykazano, że zastosowanie sytemu wielowarstwowego nanoszenia na podłoże ze stopu miedzi z cynkiem cienkich powłok oraz jednowarstwowych powłok z cienką warstwą pośrednią w procesach PVD powoduje zwiększenie odporności na korozję oraz odporności na zużycie ścierne elementów pokrytych nimi. Zbadano powłoki 1, 15 i 150-warstwowe Ti/CrN, Ti/TiAlN, Ti/ZrN, TiAlN/Mo naniesione na podłoże ze stopu miedzi z cynkiem CuZn40Pb2. Badane powłoki wykazują dobrą przyczepność do podłoża. Wzrost liczby warstw w powłoce powoduje 3¸4-krotne zwiększenie odporności na korozję. Optymalne własności mechaniczne oraz odporność na zużycie ścierne uzyskano dla powłok jednowarstwowych z cienką pośrednią warstwą czystego tytanu mającą na celu redukcję naprężeń i ograniczenie propagacji pęknięć na granicy powłoka-podłoże, natomiast wzrost liczby warstw do 15 lub 150 powoduje ich spadek. Dobra odporność powłok PVD podczas działania czynników zewnętrznych potwierdza celowość pokrywania nimi przedmiotów użytkowych. Jednocześnie wykazano, że nie można opracować "uniwersalnej" powłoki, a na jej wybór i zastosowanie podstawowy wpływ będzie mieć analiza warunków eksploatacji powłoki.

EN

It has been shown that the employment of the multilayer system of thin layers and monolayers with a thin intermediate layer onto copper and zinc alloy substrate using the PVD method results in an increased corrosion and wear resistance of elements covered with these layers. Coatings with 1, 15, and 150 layers of Ti/CrN, Ti/TiAlN, Ti/ZrN, TiAlN/Mo deposited on CuZn40Pb2 brass were examined. The examined coatings demonstrate good adhesion to the substrate. The increase of the number of layers in a coating results in its corrosion resistance improvement by 3÷4 times. The optimal mechanical properties and wear resistance were obtained with the single layer coatings with a thin intermediate layer of pure titanium used for stress reduction and for limiting the propagation of cracks on the coating-substrate boundary, whereas the increase of the number of layers to 15 or 150 results in the deterioration of these properties. The good resistance of the PVD coatings when subjected to external factors confirms their usefulness for articles of general use. It has also been demonstrated that is not feasible to develop an "all purpose" coating, and an analysis of the operating conditions of the coating has a fundamental influence on its selection and application.