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  • Author or Editor: D. Nagy x
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This is a brief history of how a small group of people carried out its mandate to survey and map Canada in spite of the hostile environment — the second largest country in the world — in a 100 years.The levelling started from Halifax and by 1916 it reached Vancouver completing the coast-to-coast connection, encompassing about 22 000 km distance of which 94% was done on the railway tracks. The adjustment was carried out in 9 steps, it included the tide gauges in both the east and west coast, and was completed in 1928. The final adjustment used about 37 000 km length, from which 30 000 was measured by the GS. The first order re-levelling started after the Second World War and was carried out on the Trans-Canada highway. By 1994 Canada was covered by a levelling network of about 109 747 km. After this date there was no more conventional levelling.The triangulation used cross-braced quadrilaterals, based on the method used in the USA. In 1961 the GS started to use the conventional methods of chains of triangles. The measurements covered mostly the very southern part of Canada. The mapping of middle and northern part of the country had to await until the electronic era, which was practically made for Canada.The lower order accuracy was provided by Shoran, using about the average of 400 km line length for triangulation. Between 1947 and 1957 this method provided 501 measured triangle sides of about 200 000 km in total length and provided 119 base-point covering about 65% of Canada.The other method, the Aerodist — the Tellurometer version of Shoran — provided second order accuracy. The triangulation, using cross-braced quadrilaterals, with 100 km sides gave 219 points and covered about 25% of the land area of Canada. The measurements were done between 1965 and 1973.Recent measurements make use of GPS for geodetic position determination. A 10 year program started in 1987. In 1992 the GSD defined an official geoid to be used in connection with all satellite work.

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Abstract  

Samples of full blood of vitiligo patients and those of control persons were analyzed for Se, Cr, Co and Ni contents by neutron activation analysis. The concentrations are reported in ppm/dry weight. The results showed that the Se and Co levels were significantly higher in the blood of vitiligo patients while the increase of Cr and Ni was not significant as compared to the controls.

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The study area is the peaty bed of Nyíres-tó mire which is situated in the northeastern Alföld on the Bereg Plain. For this paper we used a digital photo interpretation method with which we reconstructed the former vegetation from black and white aerial photos, and made chronosequence of vegetation maps. The image segmentation method dissolves the photo into different objects (segments) by spectral and textural parameters. The segments consist of similar pixels, representing a unique ground object. We made the segmentation with the Definiens Inc. eCognition software. The stability of the mire was calculated with GRID-files. The historical vegetation maps show, that after many arid years, the tree or shrub dominant associations increased until the eighties. Later, the sufficient precipitation and the artificial flooding stabilised the tree covering. The analysis of GRID-files shown, that 45.77% of the pixels get code 1 (stable), 44.32% get code 2 (slightly changeable) and only 9.91% get code 3 (changeable). It means that almost half of the mire’s vegetation is the same as in 1952.

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The study area is the peaty bed of Navad-patak mire situated in the North-Eastern Alföld, on the Bereg plain, which is slightly investigated area. The purpose of our research was to reconstruct the recent vegetation dynamic processes of the mire from 1950 till 2005. Beside the aerial photos we used the ERDAS Imagination remote sensing program, and made digital photo interpretation. We divided the vegetation history into three parts. In the first period, the nutrient load of the mire was increased, peat decaying and foresting processes started, the open peat-moss dominated associations ( Eriophoro vaginati-Sphagnetum, Carici lasiocarpae-Sphagnetum ) were disappeared. In the second period the expansion of the forest vegetation continued, the species composition transformed, and the characteristic species of the mentioned associations ( Eriophorum vaginatum, E. angustifolium, Carex lasiocarpa, Drosera rotundifolia, Sphagnum magellanicum ) were all disappeared. The third period starts with the artificial flooding in 1994. In the beginning the peat-mosses were all extinct, floating mires appeared immediately and their quick succession started and still runs. The fourth period would be start with the appearance of peat-mosses.

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The paper presents significant aspects regarding the concept and details of constructive solutions used to design and implement an energy efficient school building in Romania. Although the site is in a moderate seismic zone, the structural needs of the building impose specific insulation solutions for making the passive house concept applicable. Renewable energy sources are also applied to optimize the maintenance cost and to reduce the payback period to a feasible level. In order to prove the benefits of the solutions, to justify the higher initial investment, to improve the real-time energy consumption of the building, as well as to keep track of the internal climate parameters, a complex monitoring system was planned and implemented. Details and correlation between specific details and temperature sensors distribution are also presented.

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Thermal properties of ammonium nitrate

I. Study of the reproducibility of DTA curves in relation to modification transformation

Journal of Thermal Analysis and Calorimetry
Authors: E. Jóna, T. Šramko, and D. Nagy
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Abstract  

A control system for monitoring the radioactive concentration in aqueous wastes of nuclear installations was elaborated. The mobile station developed for in situ control enables simultaneous measurement of gamma radiation in the energy range of 0.15–2.0 MeV and that of beta radiation in the energy range of 0.3–2.0 MeV by means of a combined scintillation detector. Disturbing effects of accompanying and secundary radiations on the determination of the counting efficiency vs. radiation energy functions used in calculation of the radioactive concentration limits as well as some experiences during a long time of operation of the system have been discussed.

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Mutations in the HIV-1 pol gene associated with resistance to antiretroviral drugs in therapy-naïve Hungarian individuals transmitted as primary infection by their foreign sexual partners originated from African, Asian and other European countries had been analyzed. Drug resistance genotyping of HIV RT and PR genes were performed where mutations of 72 codons — among them 64 specific resistance codons representing 6 nucleoside reverse transcriptase inhibitor (NRTIs), 2 non-nucleoside reverse transcriptase inhibitor (NNRTIs) and 6 proteinase inhibitor (PRIs) drugs — had been analyzed by Truegene HIV-1 Genotyping kit and OpenGene Sequencing System. Viral variants harboring resistance mutations in the po l gene were detected in 14% of the subjects. The highest rate of resistance to a single class of inhibitors was detected towards PR inhibitors (12%), followed by NRTI (8%) and NNRTI (5%). On the contrary, 25% of viruses transmitted by homosexual activity contained mutations led to resistance to NNRT. Viruses from 11 percent of cases were resistant to 2 classes of inhibitors, and 7 percent to three classes of inhibitors. Based upon sequence data non-B subtypes and CRFs were detected in more than 71% of cases. HIV-1 C (10.7%), HIV-F1 (7.2%) and HIV-1 G (3.6%) were detected as the more frequent subtypes. Among the HIV-1 recombinant viruses CRF02_AG variants were found more frequently (28.5%) followed by CRF06_cpx (17.8%) indicating penetration of non-B subtypes and recombinant African variants into Hungary, which raises serious clinical and public health consequences.

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In the microflora of sunflower seeds stored in domestic stores the, Alternaria species dominate, while those of Penicillium, Trichoderma, Stemphylium and Absidia spp. are present in lower numbers. During model tests (cca 20% seed moisture content, 25 °C, 4 weeks storage) the Alternaria species were almost completely eliminated and on the seeds mainly Aspergillus species, characteristic of stores, propagated. The moulds significantly deteriorated the quality of the seed and that of the produced oil and meal (reproductive ability, germinating power, oil content, lipoxygenase enzyme activity, acid value, peroxide value, fatty acid composition, UV absorbance, colour, sensorial properties, as well as the protein content, amino acid composition, colour and the smell of the meal), but no aflatoxin production occurred. The findings offer a comprehensive picture on the multiple destructive effects of incorrect storage.

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