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A new model for predicting carbon storage dynamics and emissions related to the waste management of wood products: introduction of the HWP-RIAL model
75-81Views:151The ability of wood products to store carbon allows for their significant contribution to the climate mitigation efforts and the emission reduction commitments set by the EU. In order to optimise the carbon storage capacity of wood products, it is important to take climate mitigation aspects into consideration as much as possible during their production, use and waste management. The aim of this study was to quantify the effects of product development, recycling, and waste management technologies on carbon storage and emissions. In the frame of the ForestLab project, a new model and decision support tool was developed, which is able to predict the duration of carbon storage of wood products and the evolution of emissions from them. The developed HWP-RIAL model (Harvested Wood Product Recycling, Incineration And Landfill model) uses the methodology of the Intergovernmental Panel on Climate Change (IPCC) to calculate emissions, which is also used in the National Greenhouse Gas Inventory report. It combines the IPCC waste model with equations describing the carbon storage and emissions of wood products, and the model is also supplemented with a self-developed recycling and waste routing module. This paper provides insight into the operation of the model by following the life cycle of 200,000 m3 particle board.
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Estimation of direct and maternal genetic parameters for weaning weight in Hungarian Simmental cattle
17-22Views:175The aim of the current research was to estimate variance components and genetic parameters of weaning weight in Hungarian Simmental cattle. Weaning weight records were obtained from the Association of Hungarian Simmental Breeders. The dataset comprised of 44,278 animals born from 1975 to 2020. The data was analyzed using the restricted maximum likelihood methodology of the Wombat software. We fitted a total of six models to the weaning weight data of Hungarian Simmental cattle. Models ranged from a simple model with animals as the only random effect to a model that had maternal environmental effects as additional random effects as well as direct maternal genetic covariance. Fixed effects in the model comprised of herd, birth year, calving order and sex. Likelihood ratio test was used to determine the best fit model for the data. Results indicated that allowing for direct-maternal genetic covariance increases the direct and maternal effect dramatically. The best fit model had direct and maternal genetic effects as the only random effect with non-zero direct-maternal genetic correlation. Direct heritability, maternal heritability and direct maternal correlation of the best fit model was 0.57, 0.16 and -0.78 respectively. The result indicates that problem of (co-)sampling variation occurs when attempting to partition additive genetic variance into direct and maternal components.
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A simplified growing model for mixed black locust (Robinia pseudoacacia L.) and poplar (Populus spp.) plantations in the Danube-Tisza Interfluve
97-100Views:150This study presents a static model of mixed black locust (Robinia pseudoacacia L.) plantation stand structures for inventory stand structures between 10 and 40 years of age. Due to its local character, the model can be advantageous in planning tending operations, making structural factor predictions for the standing stock (main stand) after tending cuts, and preparing local wood production and silvicultural models. The model data presented in this paper show that poplars account for 55–62 % of the volume per hectare due to their faster growth rate in mixed black locust and poplar plantations. Maintaining the black locust part of the stand necessitates harvesting the poplars by the age of 10 at the latest.
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Conceptional Model of Regional Agricultural Water Management System
199-209Views:126Our study focuses on the water management improvement of the Hajdúsági-löszhát (loess ridge). The Hajdúsági-löszhát (loess ridge) is an intensive agricultural area. At the same time, the problem of increasing water demand is still not solved, so towards of safety production irrigation should be improved. To realise this should be known not even agricultural water demands but industrial and urban ones as well, thus a complex water management system is required to be worked out.
In the first part of the research, the water demand in the area is mapped, then a conceptional model of the Hajdúsági-löszhát’s (loess ridge’s) water management system is created. After collecting data the water management scenario is summarized in a real time model splitted into five periods.
During the research, the instruments of spatial informatics (GIS) are used to get acquainted with the variation of the hydrological parameters in space and time. To understand and simulate the different decision making processes and to choose the right decision alternative, a decision support system is created with the use of spatial informatics data.
In addition, considering the potentially right decision alternative, irrigation will be started in practice, an effect and after-effect inquiry will be made, and the results will be analysed, evaluated and summarized. Finally, a suggestion to the most adequate irrigation technology will be made. -
Analyzing the Efficiency of Dairy Farms by Using the Method of Data Envelopment Analysis (DEA)
17-21Views:116In Hungary the dairy sector is in a long-term critical period, the stock has been in constant decline. The consumption of milk and dairy products in Hungary is slightly rising compared to the world tendency, and it is fallen behind the level in 1990. The milk consumption per capita in 2006 was with 75 liters less than the EU-15 average. Dairy enterprise is a very risky activity: the profitability of the enterprise is affected by the fluctuation of feed and animal health products prices from the side of inputs, and by the fluctuation of end-product prices. Under these circumstances it is vital for the
cattle breeders, in order to survive, to harness the reserves in the breeding as effectively as possible. In our research we made a multi-faceted efficiency analysis of an agricultural holding’s three dairy farms. The chosen method for the analysis was Data Envelopment Analysis (DEA). The
selection of the method is justified by the fact that there is not such a reliable database by which we could define production functions, and that DEA makes possible to manage several inputs and outputs, i.e. multiple decision problems, simultaneously. By using DEA the sources that causes shortfalls can be identified, analyzed and quantified on farms that does not operate efficiently, thus it can help the corporate decision support successfully. In the model inputs are the cost data per one liter milk – feed, medicinal product use, logistic costs -, and the main parameters
concerning the keeping and rearing. Outputs are indicators concerning milk production, milk quality and others. We prepared the model in MS Excel, the linear programming model series were programmed by Visual Basic. After solving the model, in light of the shadow prices we can determine why either of the farms is not efficient. -
Methods for the examination of the role of the time factor in managerial and organizational processes
24-32Views:76managerial efficiency. The system of investigations is in accordance with the method elaborated and applied by the Department of Management Science of UD, CAS, Faculty of Agricultural Economics and Rural Development (Berde, 2003). This method involves questionnaire interviews and corporate data collection. The first part of the questionnaire contains data with respect to the company, while the second part focuses on the manager being interviewed. The third part is a closed, directed interview-based preference assessment. I aim to assess the sample at my disposal in order to test the research model.
In the course of the assessment of questionnaires, I apply descriptive statistical methods for the assessment of the personal and professional features of the managers interviewed and the characteristics of the companies. In the case of questions substantively concerning the time factor – resource, managerial function, reaction time, and impact assessments – I carry out hypothesis testing. I draw up a zero hypothesis, whose appropriateness I test by means of statistical methods. I usually apply rank correlation for the evaluation of the relationship between the variables measured on an ordinal scale in my investigations. This can be applied if not the exact values of the given variables, but only their order in one respect or another is known. If the group building criterion is two-variable Mann-Whimey, if a multi-variable Kruskal-Wallis trial can be applied, which, after the rank transformation, gives information about the acceptance or refusal of the Ho hypothesis through the average of the ranks. The model also contains the managers’ evaluation of the time factor in management work. -
The development of the scientific bases of horticulture and the history of horticultural innovation in the Northern Great Plain region and in Debrecen
17-20Views:90It can be told about the second half of the XXth century that, apart from preferring the large-scale growing of field plants and the largescale
livestock farming, corresponding to the central political will of the communist era, the significance and innovation output of
horticultural education in Debrecen was rather of follow-up trait, of secondary importance. The Tobacco Research Institute continued the
research work, and then even this activity was stopped. According to a survey finished in 1997, the mentioned institute had no invention,
granted patent, protection for registered model or any application for patent in progress at the Hungarian Patent Office. Until this time, invention activity at the University of Agricultural Sciences was of medium standard. In the National Patent Office, seven patent applications related to agricultural production and nine patent applications for other fields submitted under the inventors’ names were recorded. In the same period, the Cereal Research Institute (Szeged) led the absolute innovation list of Hungarian agricultural R+D institutions and university education institutes by submitting 164 own patent applications. Both in domestic and international terms, the horticultural innovation conducted at the University of Agricultural Sciences, despite the individual research results and achievements deserving recognition, without appropriate background – remained unnoticed. Let us put it this way: for the past decades, the light of the Debrecen Flower Carnival has not been thrown on the horticultural teachers and researchers of Debrecen. -
Timing it right: The Measurement and Prediction of Flowering
17-22Views:76Although the model described here was developed from research in controlled environments, there is now considerable evidence that in can be applied to a very wide range of natural environments in several species. Multi-locational trials augmented by successional sowing and, if considered necessary, supplementary illumination in the field to increase daylength, can be used to estimate the values of the model coefficients: (1) to characterize germplasm collections and so predict flowering behaviour elsewhere; (2) for interpreting and understanding crop adaptation; and (3) for genetic analysis of photoperiod sensitivity. We do not yet know whether the model has any contribution to make to the understanding of the biochemical mechanisms of photoperiod and temperature responses, but at the very least, it should provide the basis for indicating the most appropriate environmental conditions, genotypes and physiological stage of the plants most suitable for such investigations.
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Biomass production estimation of processing tomato using AquaCrop under different irrigation treatments
131-136Views:215The wiser usage of irrigation water is inevitable in the future. Irrigation has very high input cost; therefore, farmers must carry out irrigation with care. Also, the effect of irrigation on crops has a big role in decision making. Modeling provides a possibility to evaluate this effect. AquaCrop, as a crop production simulation model has great potential in this field. The accuracy of tomato biomass yield prediction of the model was tested in this research. For collecting the necessary data, a field experiment was conducted at Szarvas on processing tomato with different water supplies, such as 100% (I100), 75% (I75), 50% (I50) of potential evapotranspiration and a control with basic water supply (C). The relation of the simulation and actual biomass yields was evaluated during the season. Very good correlation was found between the modelled and the actually harvested data. The data for the control and I100 treatments showed higher correlation than the I75 and I50. The relationship for all of the data was moderately strong. Miscalculations occur mostly when the dry biomass yield reaches
7 t ha-1. The accuracy of the model was evaluated with the use of mean absolute error (MAE) and root mean squared error (RMSE) values. The least error was found in the C treatment, which means 0.34 MAE and 0.45 t ha-1 RMSE. The simulation resulted in higher errors in the I75 and I50 treatments. -
Preparatory study for carbon sequestration modelling of agroforestry systems in Hungary: The assessment of the yield class distribution of windbreaks
73-78Views:83The escalating carbon dioxide emissions leading to global climate change are acknowledged as a paramount environmental challenge in the twenty-first century. The significance of land use systems in stabilising carbon dioxide levels and enhancing carbon sink potential has gained noteworthy attention from both the scientific and political communities. The Intergovernmental Panel on Climate Change emphasises that agroforestry systems present vital prospects for synergising climate change adaptation and mitigation efforts, offering substantial technical mitigation potential. Windbreaks are well-known agroforestry systems in Hungary and form an important part of agricultural landscapes. The improved agroforestry subsidy system in our country makes it relevant to model the carbon sequestration potential of windbreaks. In the framework of the ForestLab project we plan to develop a carbon sequestration model specific for Hungarian agroforestry systems. In this study, as a preparatory step of the model development, we assessed the yield class distribution of Hungarian windbreaks by tree species group and identified variables that had significant effect on yield class based on the data of the National Forestry Database. Our results show that among the examined effects the most important predictor of the yield class of windbreaks was the tree species group, followed by the thickness of the productive soil layer and the hydrology of the site.
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Estimating Genetic Parameters using a Random Regression Model
53-55Views:135One of the most important part of the genetic evaluation using a random regression model is the estimation of variance components. This is the topic of many papers because the large computational costs. We can use restricted maximum likelihood (REML), Gibbs sampling and ℜ method for the estimation of genetic parameters. The variance components are necessary to calculate the heritabilities and repeatabilities.
The aim of our paper is to estimate the variance components using a random regression repeatability model from test day data set of Hungarian Holstein-Friesian dairy cows and to analyse the change of additive genetic and permanent environmental variance, heritability and repeatability over lactation. -
Examination of the Effect of Transaction Costs in the Hungarian Beef Sector
212-223Views:78technical and economic characteristics, which give rise to high levels of uncertainty and greater control in the supply chain. In order to investigate the role of different transaction costs in marketing behavior, we carried out research in the central region of Hungary among beef retailers and wholesalers. This research is based on primary data collection and examines the motivation of choices in the beef sector on distinction among different marketing channels and the role of transaction costs in procurement. Since this case can be regarded as a qualitative choice situation the hypothesis that transaction cost’s variables are significant is judged by the application of multinomial logit model in order come up with the variables that can influence the supply chain structure and the choice of different marketing channels. This analysis enabled us to explore the structure in data and confirm or reject the expected interrelations of causative variables. Our
1 A szerző témavezetője Dr. Fertő Imre.
2 A kutatás az OTKA F038082 sz. „Vertikális koordinációs és integrációs modellek az élelmiszer-gazdaságban” c. programja keretében valósult meg.
3 A szerző köszöni Dr. Fertő Imrének és Dr. Szabó G. Gábornak, a Magyar Tudományos Akadémia Közgazdaságtudományi Kutatóközpont tudományos főmunkatársainak a kutatás során nyújtott nagy értékű segítséget. results partly support and contradict the basic predictions of transaction cost economics. -
Mathematical modelling of surface irrigation for field crops in Jordan based on soil hydrological-physical properties
137-148Views:106Jordan suffers from drought and depletion of water resources. In-field crop management, the issue of irrigation scheduling is important and influential. In this research note, a simple method was developed for scheduling surface irrigation of field crops based on inputs of crop ecology, effective root depth, soil texture, soil hydrology, and logical mathematics. It was concluded that the science of mathematics has succeeded to meet academic irrigation scheduling in terms of surface irrigation for field crops based on both soil hydrological and physical traits. Extension scholar has a decision to choose mathematical irrigation model depends on the traditional inputs or updating the model by searching for renewable inputs such as different varieties root depths, optimum row spacing of each crop, drip irrigation mathematical modelling, and digital sensing. In both cases, the input related to the effective root depth is a major and basic factor in mathematical irrigation scheduling. It is, therefore, recommendable that extension research-based systems should focus on basic mathematics to capacitate the complementary role of academics, research, and extension in irrigation modelling, and rural development.
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Examination of the effect of pelleted poultry manure products on a sunflower test plant in a laboratory model experiment
83-88Views:247Sunflower (Helianthus annuus L.) is one of the most important oil plants in Hungary, with a sown area of more than 627.000 ha in 2019. Sunflower cultivation is primarily important for use in the oil industry, but its role in feed and beekeeping cannot be neglected either. Sunflower adapts well to different production areas in terms of soil demand, yet, as important fact, it must be grown on soils with poorer conditions with intensive nutrient replenishment. From the agri-environmental point of view, in addition to the use of pelleted poultry manure products, which are also new to the consumer market, is of paramount importance. Their advantages include a wide range of nutrients as well as a soil structure improving effect.
In our research, we investigated the starter effect of pelleted poultry manure products applied at different doses (200 kg ha-1 and 400 kg ha-1) on sandy soil with humus using a sunflower plant. The aim of our research to investigate the effect of using pelleted fertilizer products as starter fertilizers on sunflower plant germination, and investigate the effect of poultry manure products on soils.
Based on our results, it can be stated that the pigment content (chlorophyll and carotenoid content) was positively influenced by the higher dose treatments (400 kg ha-1), thus increasing the photosynthetically active leaf area. Compared to the control, the carotenoid content in the test plants of the treatments increased, and the differences of this treatment proved to be significant (p<0.05). Our experiments supported the beneficial effect of pelleted poultry manure-based products in the soil-plant system.
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Change of mineral and organic nitrogen forms in a long term fertilization experiment (literature)
43-47Views:127The research topic has timeliness, since the rational utilization and protection of the soil, besides the conservation of its diverse functions is part of the sustainable development. Research of the long-term experiments is esentially important, because it can model the term effects in the same place, under the same conditions. If we want to get accurate informations about the occured changes, way and danger of changes, we should track the resupply and effect of the mineral nutrients and the removed quantity of nutrients with the harvest. Nitrogen is an essential element for living organisms, it is present in the soil mainly in organic form. In general only only a low percentage of the total nitrogent content can be used directly by plants in the soil. This inorganic nitrogen is produced by the transformation of organic contents through mineralization processes and it get into the soil by the fertilization. The plants incorporote the mineral nitrogen into our bodies. This is how nitrogen turnover is realized when mineral forms become organic and organic forms become mineral.
The purpose of our paper is to make a literature before our research.
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Sensitivity of methods for estimating reference evapotranspiration
51-56Views:159The knowledge of the evapotranspiration of natural ecosystems and plant populations is of fundamental importance in several branches of science, research topics and practical uses. Nevertheless, the harmonization of the large number of methods and the changing user needs often causes problems. Sensitivity analysis of 10 ET0 estimation models and model variants was performed. Magnitude of the obtained outputs and the changes triggered by each atmospheric parameter were evaluated. The objective of the analyses was to get to know the sensitivity of the different models and to select the most accurate and the most suitable ones for adaptation to local circumstances. Therefore, it becomes possible to achieve as high accuracy as possible in applications which need ET0 estimation.
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Complex assessment of inland water fish stocks
74-80Views:102In the domestic fish production, natural waters have yielded for several years about 7-8 thousand tons. This, from the point of view of outputs, considering the almost 130 thousand hectares of natural water, is rather low, it means approximately 55-60 kg/ha mixed fish.Although the various natural waters can differ significantly on the basis of yields, yet on the majority of the territories, the results were low. In the case of our extensive still waters and rivers, the reason can undoubtedly be found in the combined effect of the lack of the possibility of reproduction of the fish stock and the over-fishing. Fishery built on planning supposes the best possible knowledge in the given circum stances of the parameters of the water area and its fishstock. Lacking this knowledge, it is not possible to establish the optimal use fulness of the resources, what is more, the management can make faulty decisions – as a result of a lack of information -, which can risk the success of later activities.
It is known that many factors have an impact on the success of the fishery, as well as some information in connection with the water area and the fish stock are necessary, the knowledge of which make it possible to manage the fishery in a planned way. One part of the information is available, while the other part is incomplete or not deep enough. The necessary data are dissimilar depending on their nature, can be obtained from different places, by different methods.
As the first step for executing the field surveys and processing data, I developed a complex model, which contains in a unified system the steps of estimating the fishstock. I made the sampling on the basis of this. Part of the model is a fish faunistic survey, as well as a morphological survey of the water area. The information gained from these are important for making more accurate the system of devices of the samplings for stock estimation (duration, number of net-rows) and for assigning its place (places representing the best way the physical characteristics of the given water area). The major stages of stock-survey: A) faunistic survey, B) physical survey of the bed, and C) sampling with the help of gill-nets. This is followed by the evaluation by the computer module.
The results of the research create a methodological and technical background for the fish faunistic and population biologic surveys still performed in different ways in our country, and by applying these methods together, all basic information about natural waters which help decision-making concerning fisheries can be obtaine deffectively. -
Case study based analyses of economic viability of Hungarian beef farms
184-193Views:112Our country has great traditions in the field of beef production. As early as the Middle Ages, Hungary was known as Europe’s beef exporter. In this decade, production of the Hungarian Grey has increased, due to the popular method of keeping these animals extensively. These animals were even exported to the European markets on foot.
After joining the European Union, this sector of agriculture has been receiving attention due to the major subsidies which were given. Accordingly, numerous farmers have tried to enter this sector of production. However, the power relations have been changed lately, as have the technology used in production, which has undergone several developments. The integrative connections in the sector had been split and also the size of optimal and sustainable production has arisen.
The economic activities must be judged by their effectiveness and profitability, but in most cases their effectiveness can only be seen through such outstanding facts which are independent from the farmer.
I would like to model the economy of a certain enterprise, and the size and the level of its production, through my research under the actual economic circumstances. In my research, I pay special attention to the circumstances which are important in the Hungarian agricultural sector and rural development. -
Water managed properties of apple and pear trees based on lysimeters
129-132Views:176A significant proportion of the aboveground green and dry weight of the plant is constituted by foliage. The canopy is an important factor of plant growth. On the one hand, the canopy absorbs solar energy, which is necessary for photosynthesis; on the other hand, it accumulates the nutrients absorbed by the roots, and most of the water-loss occurs through the foliage. The determination of the full canopy is not an easy target. In our research, we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of the ADC AM 100 leaf area scanner, we determined the k-value, with which we can easily and fast evaluate the leaf surface. Furthermore, we defined from the water balance of compensation lysimeters the cumulative transpiration of fruit trees and the efficiency of water use of trees. From the examined trees were made a 3D depiction, which show the shape, branching and the location of trees.
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Study on the weeds of maize in the infected field with Cirsium arvense (l.) scop.
131-135Views:128The aim of our research was to establish the difference between the weed flora of maize hybrids sown in different times. Our field trial has been performed nearby Szombathely on a field of an agricultural farm, where two different hybrids were grown. The cold tolerant hybrid was sown at the end of March; the traditional hybrid was sown at the end of April. During the vegetation weed survey was conducted on 4–4 model parcels at two times in case of both hybrids. Cirsium arvense gave the largest weed cover in both hybrids. In cold tolerant hybrid gave 4.53%, in the traditional hybrid gave 56.63% weed cover. Considering the number of shoots per square meter C. arvense was also dominant with 64 plant m-2 density in early sown maize and 49.5 plant m-2 in traditional maize hybrid. At the time of the second weed survey the number of weeds increased significantly. The shoot number of C. arvense in cold tolerant hybrid was almost one and a half times more than at the first evaluation, while in case of the traditional hybrid it is nearly doubled. According to the weed density assessment there were differences between the two hybrids in the rate of G3 and T4 weeds. In early sown maize hybrid (MT Milo) this rate was 50–50% while in traditional hybrid was 90–10%. On 26th June the density of the weeds in the cold tolerant hybrid was two times higher than in the traditional one (Kamelias). Based on the experimental results it can be stated that the effective weed control in cold tolerant, early sowing maize hybrids is very important too.
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Effect of cadmium and zinc contamination on the population dynamics of soil microorgani
73-77Views:124Changes in the population dynamics of microorganisms in a soil artificially contaminated with various doses of cadmium and zinc was examined from a quantitative point of view, under laboratory circumstances. The research was based on a chernozem soil originating from the area of a long-term microelement contamination model experiment (Nagyhörcsökpuszta, Hungary), which was carried out during 1991 in the Experimental Site of the Institute of Soil Science and Agricultural Chemistry, Centre for Agricultural Researche Hungarian Academy of Sciences, Budapest, Hungary. According to the amount of bacteria, microscopic fungi and nitrifying bacteria, it can be stated that the effect of contamination can be observed even in the perspective of nearly two decades. In more cases significant changes in the number of soil bacteria and microscopic fungi could be observed, and the nitrification activity increased in case of both microelements. Therefore the further research of changes in microbial activity of these soils can provide novel scientific results.
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Penicillium chrysogenum antifungal protein (PAF) production in transgenic tobacco (Nicotiana tabacum) plant
77-82Views:113Under the „Molecular farming” research program (product vaccines and substances for medical use with gene manipulated plant) in 2007 in UD Centre for Agricultural Sciences and Engineering Faculty of Agricultural Science Institute of Horticulture Department of Plant Biotechnology experiments were launched to transform tobacco plant by PAF antifungal protein. Our aim was to learn the transformation technics. We chose the
Nicotiana tabacum and PAF as model systems.
Our work was to express several different paf constructions in plants with nuclear and plastid transformation too. After that we confirmed the presence of paf gene in the level of DNA and RNA. -
Application of time series in medical research
14-22Views:90This article reviews the mortality data of chronic liver disease and cirrhosis, as well as tracheal, bronchial and lung cancers, in Hungary by methods of time series analysis. The methods of time series of death rates of chronic liver disease and cirrhosis as well as tracheal, bronchial and lung cancers and their reliability, are analysed from data available from WHO. The author used ARIMA models (autoregressive and integrated moving average models) and auto- and cross-correlation functions to study the substantial role an exogenous environmental factor has on incidences of
death. The confidence intervals of autoregressive (AR) coefficient are compared to the standard normal distribution, the estimation of White’s theory and the continuous time estimation model.
On the basis of the analysis, it may be concluded that chronic liver disease and cirrhosis can be influenced by an exogenous environmental factor, however, this relation cannot be demonstrated for deaths due to tracheal, bronchial or lung cancers. In each case, the continuous estimation of the AR(1) coefficients give the best results.
The paper demonstrates how the presented methods can be applied to agricultural science. -
Competitiveness of the biomethane opposite with the CHP technology of biogas by definite plant size
5-9Views:131The biogas sector has never before aroused so much attention as it does today. Combined heat and power (CHP) reliable and cost-effective technologies that are already making an important contribution to meeting global heat and electricity demand. Due to enhanced energy supply efficiency and utilisation of waste heat renewable energy resources, CHP, particularly together with district heating and cooling (DHC), is an important part of national and regional Green House Gas (GHG) emission reduction strategies.
During my work I am going to use the basic data of a certain biogas plant than I assemble one model from that. Against the CHP technology I am going to plan a biogas cleaning-equipment. During my research it revealed, that in the case of a 1 MW output power plant it is not worthy to deal with biogas cleaning between national conditions. Investigating the quantity of heat recovery in the CHP technology it is obvious, that the net income at 1 m3 biogas is at least 72 times more than the cleaning technology (heat recovery is 0%).
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Effect of Soil Covering on the Soil Enzyme Activity of Integrated Orchard
20-29Views:95The purpose of our experiments is to discover the effect of different soil cover matters (agrofoil and black polyethylene) on the activity of some enzymes (phosphatase, saccharase, urease, catalase, dehydrogenase) occuring in soil. Soil samples were taken from a cider apple plantation of the Fruit Producing Research and Advisory Kht Újfehértó. The enzyme activity was measured according to Krámer and Erdei (1959a), Kuprevič and Tsherbakova (1956), Kuprevič et al. (1966), Frankenberger and Johanson (1983), Mersi and Schinner (1991). Soil moisture content was by conventional (drying chamber) method measured during every sampling and enzyme activity was transpolated to absolute dry soil. Results were estimated by mathematical methods (variation analysis, correlation counting). Soil samples were taken by trials 5 times (in every two months) a year in the vegetation period from March to November.
By recording the monthly changes of the enzyme activity we have observed the following. The activity of the phosphatase was generally the highest in May and the lowest in November. Depending on the trials, high values were also measured in March and September. The activity of the saccharase was generally the highest in November and the lowest in June, but at the same time peaks even occured in May and September. The highest urease avtivity was measured in September and November, and the lowest activity in May and July, also depending on the trials. In the year 2000, after a deep point in March, the activity of the catalase was the highest in November or by certain trials in September. In 2001, the lowest activity was also measured in March, but the highest activity appeared in November in case of one-minute trial, and in May in consequence of two-minute trial. Finally the activity of dehydrogenase was the highest in November and the lowest in July apart from the model years.
There were essential differences in rainfall of the two experimental years which was reflected in the enzyme activities. There was a poor positive significant relationship between soil moisture content and enzyme activity values in case of phosphatase, saccharase, urease (r=0,426; 0,480; 0,396) respectively. In case of catalase1 (r=0,518), catalase (r=0,556), dehydrogenase (r=0,559) we obtained a medium strong positive relationship between soil moisture content and enzyme activity values. By evaluating the effect of different trials in case of every examined enzyme significantly higher values were detected in soils covered by agrofoil (a porous black polyethylene) than in soils covered by black polyethylene or in uncovered soils. Moreover, the soil covered by black polyethylene showed significantly higher enzyme activities (besides phosphatase) than the control soil. Thus soil-covering meant statistically significant advantages in enzyme activity as opposed to uncovered soil proved.