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The amount of sand moving parallel to a coastline forms a prerequisite for many harbor design projects. Such information is currently obtained through various empirical formulae. Despite so many works in the past, an accurate and reliable estimation of the rate of sand drift has still remained a problem. It is a non-linear process and can be described by chaotic time-series. The current study addresses this issue through the use of Adaptive Neuro-Fuzzy Inference System (ANFIS). ANFIS is about taking an initial fuzzy inference system (FIS) and tuning it with a back propagation algorithm based on the collection of input-output data. ANFIS was developed to predict the sand drift from a variety of causative variables. The structure and algorithm of ANFIS for predicting the rate of sand drift is described. The Adaptive Neuro-Fuzzy Inference System was validated by confi rming its consistency with a database of specifi ed physical process.
As a result of plant tissue deformation irreversible physical processes that finally lead to the state of resistance, take place. One of these irreversible processes is cracking of the cell structure that occurs through cell wall breaking and losing cohesion in the layer of pectin lamella. As a result of these phenomena a signal of acoustic emission is emitted. In the present study the method of acoustic emission and its application in studying the processes of plant tissue cracking are described.
Soil organic carbon (SOC) is one of the basic soil parameters which takes part in many biological, chemical and physical soil processes and the SOC is currently considered as a key indicator of soil quality. For this reason determination of the SOC is a part of soil complex monitoring which has been performed in Slovakia since 1993. From 1993 until 2007 the “wet” method of determination of the SOC was used. Since 2008 the “dry” method for determination of the SOC has been applied. The goal of this work has been to evaluate and compare two methods of the SOC determination; the “wet”(Ťiurin method in modification of Nikitin (TN)) and the “dry” determination of the SOC by means of the CN analyser (EA), which was performed on 95 soil samples of topsoil coming from 17 sampling sites with a wide range of the SOC (1–15%). Sampling sites include arable lands and grasslands and represent main soil types and subtypes of Slovakia. On the basis of statistical processing it has been found that in soils with the SOC content up to 3%, differences between two methods are minimal. However, in the case of a higher content of the SOC, the EA method reaches a higher value than the TN method. Obtained data shows that in the case of soil samples with a higher content of the SOC, when changing an analytical method, the PTF function that reduces differences and allows to use all time series monitoring data should be used for the purpose of the tracking trends of the SOC monitoring.
The aim was to study the effect of physical processes (autoclaving/cooling cycles and spray drying) on starches having different crystalline structure: wheat (type A) or potato (type B) starch. First, the extent of changes in the physico-chemical properties of these physically-modified starches as the carbon and energy sources for growth in in vitro conditions was investigated. Characteristics of functional properties, e.g. water binding capacity (WBC), indicated that both native starches had low affinity to water, that increased however 4-times after modification. The opposite tendency was observed for fat absorption (FA). Viscosity of water dispersion dramatically decreased after modification of both starches. The ability of the tested Bifidobacterium strains to metabolise native or physically- modified wheat and potato starches was differentiated. B. pseudolongum KSI9 and B. animalis KSD29a3 isolated from animals utilised the examined starches as easily accessible substrates of fermentation, whereas B. breve ATCC 15700 isolated from human did not metabolise or only negligibly fermented starch preparations. The number of bifidobacteria populations as well as their acidifying activity were higher in the media containing wheat starch in comparison to the potato starch, whereas no significant differentiation was observed between the results obtained in media with native or modified starch. The results suggest that native or experimentally-modified wheat and potato starches with some fraction of resistant starch can be a good substrate for colonic bifidobacteria.
This paper reports on a study being undertaken to analyze the potential effects of rewetting when undertaken for the restitution of the catchment ecosystem of the Grote Nete catchment. In bringing together the expertise of both ecological and hydrological modelers, this study aims at ensuring that the science being performed is immediately relevant from both the environmental management and the socio-political perspectives. Like many European catchments, Grote Nete has been experiencing an increase in extreme hydrological events. In addition, there has been a decline in the ecological value of the catchment ecosystem. The problem is considered to be a confl ict of interests arising between urban/agricultural and nature conservation needs. Rewetting has been considered as a possible intervention to reverse these trends. However, a shortcoming with rewetting is that the hydrological consequences remain largely unknown. A numerical model has been developed to study these potential effects. A land use model, SPAN was developed and coupled to a physically- based, fully distributed model (MIKE SHE) to complete an ecohydrological model. The paper describes the development of the model.
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