Specific features of NDVI, NDWI and MNDWI as reflected in land cover categories

L

Kémiai redukciós nikkel és nikkel alapú bevonatok előállítása alumínium ötvözetek felületén = Fabrication of chemically deposited nickel and nickel base coatings on aluminium alloy surfaces

Adott funkcionális célra, gyakran csak különleges felülettechnikai módszereket alkalmazva lehet optimálisan összehangolni a hordozó (szubsztrátum) és a bevonat anyagi és műszaki jellemzőit. A projekt keretében, alumínium (AlMg2) hordozóra választottunk le négyféle felület-előkezelés után nikkel-foszfor (Ni-P) rétegeket. A ~8%-os P tartalom mellett már zömében amorf szerkezetű Ni-P bevonatok összetételét, mikroszerkezetét, porozitását, korrózióállóságát, szilárdságát, tapadását és végső soron ezektől a jellemzőktől függő lehetséges alkalmazási körét lényegesen befolyásolja az, hogy például csak a gondosan tisztított passzív vagy többé kevésbé aktív felületű AlMg2 szubsztrátumra, vagy annak cink vagy nikkel filmmel (kontakt redukciós precipitációval) bevont, azaz módosított felületére választjuk-e le a Ni-P réteget. A jelen munka keretében egy újszerű, alternatív felület-előkezelési (hipofoszfitos mártásos) módszert is kifejlesztettünk, mellyel kevesebb műveleti lépésben és az előzőekkel legalább megegyező minőségben tudtunk kiváló minőségű Ni-P bevonatokat képezni. Mintáinkat közvetlenül a bevonatképzés után, illetve néhány esetben 320 Celsius fokon (inert atmoszférában) történt hőkezelés után is, számos korszerű nagyműszeres vizsgáló módszert alkalmazva (elektrokémiai egyenáramú és váltóáramú polarizáció, SEM-EDAX, röntgen-difrakció, stb.) minősítettük. A jövőben - a sikeres előkísérleteket követően - tervezzük szemcsés anyagok (pl. SiC) kémiai nikkelezésének részletes vizsgálatát az új hipofoszfitos előkezelési módszerünket alkalmazva. | To find optimal solutions to the fabrication/construction of surface layers on given substrates for certain technival applications, it is often necessary to look for some special plating/deposition technique. In the course of this research project three different pre-treatment procedures were selected and also a novel one was developed in our laboratories in order to test their applicability and influence on the many important properties (composition, adhesion, structure, strength, porosity, corrosion resistance, etc.) of the electroless nickel-phosphorus layers, which were deposited afterwards on aluminium (AlMg2 alloy) substrates. Most of the electroless nikkel-phosphorus layers of about 8% P content had amorphous microstucture, and the ones obtained after our novel pre-treatment procedure (hypophosphite immersion) showed Ni-P layer properties very similar or even better then the ones obtained after zincate or Ni displacement type pre-treatments. Its further advantage is that it requires less processing steps then its predecessors. The materials properties of the Ni-P layers so developed were also thoroughly tested by means of different advanced testing techniques, like SEM-EDAX, X-ray diffraction analysis, and by applying many different electrochemical polarisation laboratory experimental methods as well. As a future research effort, after having some promising and preliminary laboratory experimental results, it is also planned to test the applicability of our novel pre-treatment procedure to deposit thin Ni-P films on SiC particles to be used to produce aluminium matrix composites

Characterization of Ceramic Particle Reinforced Titanium Composite Produced Via Powder Metallurgy

Nowadays, titanium is one of the most popular materials for aeronautical applications due to its good corrosion resistance, formability and strength. In this paper, rutile reinforced titanium matrix composites were produced via powder metallurgy. The steps included high energy ball milling of raw titanium and rutile powders in a planetary ball mill, which was followed by cold-pressing and sintering without external pressure. For the characterization of the milled powders and the sintered composites, scanning electron microscope, X-ray diffraction and compressive strength examinations were carried out. The results showed that the rutile has a strengthening effect on the titanium matrix. 1 wt% rutile increased the compressive strength compared to the raw titanium. Increasing the milling time of the metal matrix decreased the compressive strength values

Javaslat balanced scorecard alkalmazására az önkormányzati vagyongazdálkodásban különös tekintettel a felújításokra

After the political changeover in Hungary, local governments acquired large wealth in order to fulfill their public tasks. Moreover, National Wealth considers local governments' asset management, conservation and increase as a priority. Regrettably, local governments have failed to provide the necessary resources for the renewal of assets and investments dominate in their development policy instead of the maintanace of the assets. This study shows the main characteristics of municipal asset management and suggests Balanced Scorecard as a potential success tool for local governments in asset management with special attention to asset preservation, especially renovation projects

SPECIFIC FEATURES OF NDVI, NDWI AND MNDWI AS REFLECTED IN LAND COVER CATEGORIES

The remote sensing techniques provide a great possibility to analyze the environmental processes in local or global scale. Landsat images with their 30 m resolution are suitable among others for land cover mapping and change monitoring. In this study three spectral indices (NDVI, NDWI, MNDWI) were investigated from the aspect of land cover types: water body (W); plough land (PL); forest (F); vineyard (V); grassland (GL) and built-up areas (BU) using Landsat-7 ETM+ data. The range, the dissimilarities and the correlation of spectral indices were examined. In BU – GL – F categories similar NDVI values were calculated, but the other land cover types differed significantly. The water related indices (NDWI, MNDWI) were more effective (especially the MNDWI) to enhance water features, but the values of other categories ranged from narrower interval. Weak correlation were found among the indices due to the differences caused by the water land cover class. Statistically, most land cover types differed from each other, but in several cases similarities can be found when delineating vegetation with various water content. MNDWI was found as the most effective in highlighting water bodies

Javaslat balanced scorecard alkalmazására az önkormányzati vagyongazdálkodásban különös tekintettel a felújításokra

After the political changeover in Hungary, local governments acquired large wealth in order to fulfill their public tasks. Moreover, National Wealth considers local governments' asset management, conservation and increase as a priority. Regrettably, local governments have failed to provide the necessary resources for the renewal of assets and investments dominate in their development policy instead of the maintanace of the assets. This study shows the main characteristics of municipal asset management and suggests Balanced Scorecard as a potential success tool for local governments in asset management with special attention to asset preservation, especially renovation projects

A Novel Application of the 3D VirCA Environment: Modeling a Standard Ethological Test of Dog-Human Interactions

The concept of ‘Future Internet’, ‘Internet of Things’ and ‘3D Internet’ opens a novel way for modeling ethological tests by rebuilding models of human-animal interaction in an augmented environment as an interactive mixture of virtual actors and real human observers. On the one hand these experiments can serve as a proof of concept, as a kind of experimental validation of formal ethological models, but on the other hand they can also serve as examples for the ways a human can communicate with things (i.e., with everyday objects) in a virtual environment (e.g. on the Internet). These kinds of experiments can also support Cognitive Infocommunication related research, the field that investigates how a human can co-evolve with artificially cognitive systems through infocommunications devices. The goal of the paper is to introduce an example for such an ethological test system, a possible way for embedding a prototype ethological model described as a fuzzy automaton in MATLAB to the 3D VirCA collaborative augmented reality environment. Some details of the applied ethological experiment paradigm developed for studying the dog-owner relationship in a standard laboratory procedure, as a demonstrative example for ethological model implementation, will also be discussed briefly in this paper

A szinterelő közegek hatása a porkohászati úton előállított Ti-TiB2 kompozitok mechanikai tulajdonságára

Ebben a kutatásban 0, 1, 3, 5 tömeg% TiB2-ot tartalmazó Ti alapú kompozit mintákat állítottunk elő, három lépéses (porkeverék létrehozása, hidegzömítés, nyomás nélküli szinterelés) porkohászati módszerrel. A szintereléshez argont, illetve vákuumot alkalmaztunk és ezen szinterelési paraméter relatív sűrűségre, folyáshatárra és alakváltozó képességre kifejtett hatását vizsgáltuk. A 0 és 1 tömeg% TiB2 tartalom esetében az argonban szinterelt kompozit minták minden esetben nagyobb relatív sűrűség, folyáshatár és alakváltozó képességgel rendelkeztek, amíg a 3 és 5 tömeg% TiB2 tartalom esetében a kompozit minták közel azonos értékeket mutattak