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New methods of compost homogeneity determination in sewage sludge based compost prisms
Published October 20, 2009

There is no effective method of homogeneity measurement of compost prism. The most frequently used technology is the examination of the particle distribution. This method needs a lot of time and large number of samples. The aim of our research is establishing different effective methods to determine the homogeneity of compost prisms. During our... work, we examined the homogeneity of a prism made of sewage sludge and saw-dust mixture.
The measurements were based on the different properties of raw materials. According to this we examined the homogeneity by moisture content, heavy metal content and gas distribution measurements.
The most effective method is the measurement of gasconcentration. Although gas-concentration measurements it need special equipment it has more advantages than the other methods. The examination of gas-distribution compensates the problem of sampling because the measurement is direct. It provides the opportunity to estimate the amount of emitted toxic gases and to determine the maturity of the compost and the effectiveness of the degradation.

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Methodological development of the determination of the compost mixture ratio
Published December 22, 2010

The mixing rate of the compost raw materials basically determines the procedure of degradation. In most cases, in practice the real mixing ratio is not equal with the counted ratio – which based on the C/N ratio – and the check of the fulfilled mixing is not possible.
The homogeneity of the prism is also one of the fundamentals of the ef...fective degradation process. There is no available method to determine the homogeneity of the compost prism. 
During our research we examined the reflectance values of different compost mixtures where sewage sludge and rape-straw were used as raw materials.
According to our results we built up a regression model which gives the ability to determine the mixing rate (in 5% margin of error) and makes possible to check the homogeneity of the prism together with the access of immediate action. 

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The use of essential trace elements in the juvenile rearing of barramundi (Lates calcarifer
Published March 20, 2014

Barramundi (Lates calcarifer L.) is a predatory fish species native in Southeast Asia and Australia. Based on the geothermal potentiality of Hungary the warm-water fish can be reared successfully. Zooplankton in the wild contains minerals in a higher concentration than the usually fed newly hatched Artemia nauplii, therefore essential trace ele...ments, such as cobalt, zinc and manganese play an important role in the larviculture of barramundi. Cobalt is vital in trace amount for many living functions of vertebrates, however, lower number of papers are available considering the nutritional aspects. Nevertheless. improved growth performance was observed in cases of some fish species when diet was supplemented with CoCl2. Zinc and manganese are also vital for optimal growth and accordingly are investigated and applied diet supplements in aquaculture.

The main aim of the recent study is to investigate the effects of cobalt, manganese and zinc on the growth performance and homogeneity of fish when a commercially available dry diet is supplemented with trace elements individually and in combined treatments. A total of 6 treatments were set in a randomized blocked design where the concentrations of the applied elements were 50 mg kg-1 for CoCl2, for ZnSO4 and for MnCl2 individually, as well as for CoCl2 along with ZnSO4 and for CoCl2 along with MnCl2 in combination. Although the production parameters of larval barramundi were positively affected by the addition of trace elements when the retention of minerals occurred through nourishment living organisms, statistically no differences were found between the treatments considering the growth performance of barramundi juveniles either when dry feed was supplemented with cobalt, manganese or zinc (p>0.05). While the use of cobalt and manganese in combined treatments produced a less uniform larvae in size and as a consequence of increased heterogeneity, survival was significantly reduced by the cannibalism, the sizes distribution of barramundi juveniles wasn’t affected by the dry diet supplementation of these elements.

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Spatially Continuous GIS Analysis of Sampling Points Based on Yield and Quality Analysis of Sugar Beet (Beta vulgaris L.)
Published March 4, 2005

The homogeneity of a study area of 20x20 m used for beetroot production in North-West Hungary was analysed with geo-statistical methods on the basis of measured plant and soil parameters. Based on variogram calculations (Equation 1 and 2), the yield surface showed homogeneity in North-South direction. Considering the results, decrease of distance to 17 m can be suggested. The direction of the variability of yield (Figure 1) could be modelled with a direction variogram based on analysis of the variogram surface. In the study, developed methodological processes are presented for the analysis of spatial relationship between measured production and soil parameters. 5 spatial evaluation methods for yield surface were compared (Table 1). On the basis of the analysed methods, it can be stated that different methods (LP, RBF) should be used when the reasons for locally extreme yields are in focus than in case when the yield surface of the whole area is estimated (IDW, GP). Using adequate parameters the kriging method is applicable for both functions. Similarly to the results of an ordinary Pearson correlation analysis, spatial correlation analysis was shown using soil pH and Cu concentration data. The results of cross variogram analysis (Equation 2) and the North-South direction of the variogram surface showed negative correlation (Figure 3). Based on simulation calculations, decrease of 30% in sampling points resulted in increase of 12% in error for the total sample number considering Cu concentration. The method provides a tool to decrease the cost of sampling and sample analyses of spatially correlating features, and to increase the reliability of spatial estimation using a better sampling strategy with the same sample number.

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