The Peak Over Threshold Method (POT) was used as an alternative technique to the traditional analysis of annual discharge maxima of the Danube River. The POT method was applied to a time-series of daily discharge values covering a period of 60 years (1931-1990) at the following gauge stations: Achleiten, Kienstock, Wien, Bratislava and Nagymaros. The first part of the paper presents the use of the POT method and how it was applied to daily discharges. All mean daily discharges exceeding a defined threshold were considered in the POT analysis. Based on the POT waves independence criteria the maximum daily discharge data were selected. Two theoretical log-normal (LN) and Log-Pearson III (LP3) distributions were used to calculate the probability of exceeding annual maximum discharges. Performance of the POT method was compared to the theoretical distributions (LN, LP3). The influence of the data series length on the estimation of the N-year discharges by POT method was carried out too. Therefore, with regard to later regulations along the Danube channel bank the 40, 20 and 10-year time data series were chosen in early of the 60-year period and second analysed time data series were selected from the end of the 60-year period. Our results suggest that the POT method can provide adequate and comparable estimates of N-year discharges for more stations with short temporal coverage. and Príspevok sa zaoberá analýzou extrémnych hydrologických udalostí na Dunaji metódou Peak Over Threshold (POT). Metóda POT sa používa ako alternatíva určovania N-ročných prietokov k metóde ročných maxím pri analýzach extrémnych hydrologických udalostí. Pre výskyt vrcholových prietokov sa zvyčajne predpokladá Poissonova distribúcia. Základnými vstupnými údajmi pre štatistickú analýzu sú 60-ročné časové rady priemerných denných prietokov a 60-ročné rady maximálnych ročných prietokov v nami zvolených staniciach: Achleiten, Kienstock, Viedeň, Bratislava a Nagymaros - za obdobie 1931-1990. Extrémne hydrologické udalosti na Dunaji boli analyzované metódou POT, ktorá zahŕňa všetky maximálne denné prietoky povodní za dané obdobie, presahujúce zvolenú prahovú hodnotu. Na zostavenie teoretickej čiary prekročenia boli vybrané dve teoretické rozdelenia pravdepodobnosti: logaritmicko-normálne rozdelenie (LN) a Pearsonovo rozdelenie III. typu (LP III). Druhým cieľom príspevku bolo analyzovať vplyv zmeny dĺžky časového radu na odhad N-ročných prietokov. V práci boli 60-ročné časové rady údajov skrátené na 40, 20 a 10-ročné rady. V závere sme porovnali a zhodnotili získané výsledky štatistických odhadov N-ročných prietokov vo zvolených staniciach. Z výsledkov analýzy vyplýva, že metóda POT dáva pomerne dobré odhady N-ročných prietokov aj pre krátke časové rady údajov.
Soil and groundwater salinization are major problems for irrigated agriculture in many arid and semiarid areas of the world. Studies addressing such problems require accurate estimation of salt loadings from irrigated areas through the vadose zone to underlying groundwater. We studied Cl- transport in the vadose zone at 45 locations in a field in the San Joaquin Valley, California, through a combination of soil sampling at six depths (0-1.8 m) and numerical modeling using a coupled water flow and solute transport code (Unsatchem). Our purpose was to assess water and salt loadings from the heterogeneous field to groundwater over a two-year period, and to test applicability of the code to the data. Soil sampling in November, 1995, defined the initial water content and the Cl- concentration, and the soil hydraulic properties. Four more sampling periods, ending in November 1997, provided data for evaluating model performance. Cl- distributions in 1997 exhibited a variety of shapes including monotonically increasing or decreasing distributions versus depth, and profiles with maxima or and sigmoidal shapes. The standard modeling approach, based on the Richards equation and the convection-dispersion equation, predicted more Cl- leaching than was observed in the field. Somewhat improved predictions were obtained when the potential transpiration rate was increased by a factor of 1.5. Better leaching predictions were also obtained when the model included separate mobile and immobile water fractions, mostly by improving the profile shapes. Our study shows the importance of accurate descriptions of the lower boundary conditions, spatial variability in the water infiltration rate, and estimation of soil surface evaporation and transpiration rates. and Zasoľovanie pôdy a podzemných vôd sú hlavnými problémami pôdohospodárstva v závlahových podmienkach v mnohých arídnych a semiarídnych oblastiach sveta. Štúdie, ktoré riešia podobné problémy, vyžadujú si presné určenie zaťaženia soľami zo závlah, ktoré prechádzajú nenasýtenou oblasťou pôdy do podzemných vôd. V tejto štúdii sa zaoberáme transportom Cl- v nenasýtenej oblasti pôdy v 45 lokalitách v San Joaquin Valley, California, využívajúc kombináciu odberu vzoriek pôdy v šiestich hĺbkach (0–1.8 m) a numericakým modelovaním s využitím simulačného modelu kombinovaného transportu vody a rozpustených látok (solí) (Unsatchem). Cieľom je určenie priesaku vody a rozpustených látok z heterogénneho poľa do podzemných vôd počas dvojročného obdobia a testovanie použiteľnosti uvedeného modelu vzhľadom k vstupným hodnotám. Zo vzoriek pôdy, odobratých v novembri 1995 bolo určené počiatočné rozdelenie vlhkosti pôdy a koncentrácia Cl- , ako aj hydraulické vlastnosti pôdy. Štyri ďalšie termíny odberov, končiac v novembri 1997, poskytli údaje pre overenie modelu. Rozdelenie Cl- v roku 1997 sa vyznačovalo rozdieľnosťou tvarov, vrátane monotónne klesajúceho alebo stúpajúceho rozdelenia koncentrácií v závislosti na hĺbke, ako aj profilmi s maximom, alebo aj sigmoidálneho tvaru. Štandardný modelový prístup, založený na Richardsovej rovnici a konvektívno-disperznej rovnici, predpovedal viac vyplaveného Clako bolo pozorované v poli. O niečo lepšie výsledky boli dosiahnuté, ak sa potenciálna transpirácia zvýšila 1,5-násobne. Lepšie výsledky v prognóze vyplavovania solí boli dosiahnuté, ak model obsahoval separátne mobilnú a imobilnú vodu, predpovšetkým zlepšením tvarov vertikálnych rozdelení koncentrácií chlóru. V tejto štúdii bolo ukázané, aké je dôležité presné určenie dolných okrajových podmienok, priestorovej variability rýchlosti infiltrácie, ako aj určenie výparu z povrchu pôdy a transpirácie.
The detailed analysis of individual flood event elements, including peak discharge (Q), flood event volume (V), and flood event duration (D), is an important step for improving our understanding of complex hydrological processes. More than 2,500 flood events were defined based on the annual maximum (AM) peak discharge from 50 Slovenian gauging stations with catchment areas of between 10 and 10,000 km2 . After baseflow separation, the stations were clustered into homogeneous groups and the relationships between the flood event elements and several catchment characteristics were assessed. Different types of flood events were characteristic of different groups. The flashiness of the stream is significantly connected with mean annual precipitation and location of the station. The results indicate that some climatic factors like mean annual precipitation and catchment related attributes as for example catchment area have notable influence on the flood event elements. When assessing the dependency between the pairs of flood event elements (Q, V, D), the highest correlation coefficients were obtained for the Q-V pair. The smallest correlations or no correlations were observed between the Q and D variables.
This paper deals with some ways of carrying out an analysis of a flood event using the KINFIL hydrological model on small catchments where both land use and management play a significant role, and where these human activities can influence design discharges. The combination of GIS techniques with the KINFIL model, which is conceived on physically based infiltration approach and on a kinematic wave transformation of direct runoff, provides a tool for analysing historical rainfall-runoff events, for assessing design discharges, and for simulating some hypothetical flood scenarios. KINFIL is a complex model using the correspondence of Curve Number (CN) with soil parameters and the correspondence of kinematic wave transformation with the physiographical parameters of the Všeminka catchment in Eastern Moravia (Czech Republic), which was used in the tests. Two versions of the KINFIL model (KINFIL1, KINFIL2) were implemented. The infiltration part of the model is the same in both versions. KINFIL 1 assumes a more schematic geometrization of the catchment topography, distributing the catchment area to a V-shaped form in which a main channel collects direct runoff from both side planes or segments. This is not fully in accord with the topography of the sub-catchment. KINFIL 2 is a more sophisticated version, where the topography is GIS-organized, taking fully into account the river network and its corresponding sub-catchment division. The latter version is geographically (and also physically) better based, and the results of the simulation of the July 1997 flood waves in the Vseminka experimental catchment fit better with the observed waves. All the topographical and morphological data were analysed and prepared for the KINFIL model (particularly for the KINFIL 2 version), using GIS facilities. Thus the KINFIL 2 version can be applied in future for design discharge assessment when simulating scenarios of various land uses expressing the model parameters. and Příspěvek analyzuje povodňové případy implementace hydrologického modelu KINFIL, používaného na malých povodích, kde hospodárské využití pozemku a antropogenní vlivy hrají podstatnou roli. Záměrem příspevku je informovat o možnostech využití GIS při fragmentaci malých povodí za účelem zpřesnění vstupních dat pro hydrologický model KINFIL. Kombinace GIS a KINFIL, který je fyzikálně založen na teorii infiltrace a transformace přímého odtoku kinematickou vlnou, poskytuje nástroj pro analýzu jak historických srážko-odtokových případů, tak hypotetických scénářových simulací. Model KINFIL využívá dříve odvozených vztahů mezi hodnotami čísel odtokových křivek CN a „koncepčních“ půdních parametrů (nasycené hydraulické vodivosti a sorptivity) spolu s parametry transformace na testovaném povodí Všeminky na východní Morave. Byly testovány dvě modelové verze: KINFIL 1 a KINFIL 2. Infiltrační část modelu je v obou verzích stejná. Verze KINFIL 1 je založena na schematické geometrizaci, kde povodí je V-tvaru a do hlavního toku je sváděn přímý odtok zobou stran z paralelně uspořádaných desek a každá z těchto desek je sériově (kaskádově) členěna podle sklonu svahů. Takto definované desky ale nemusí plně respektovat členění na subpovodí. Naproti tomu nový přístup KINFIL 2, který za účelem fragmentace povodí využívá prostředků GIS, plně respektuje průběh říční sítě povodí a její členění na subpovodí. Základem pro získání požadovaných parametrů modelu KINFIL 2 je digitální model reliéfu terénu (DEM). Tato verze je geograficky lépe založená a výsledky simulovaných průtoků povodně z července 1997 na experimentálním povodí Všeminky se lépe shodují s průtoky měřenými.
Presented work concerns with a sensitivity analysis of a harmonically excited bending vibration of a rotating couple of blades with a friction element with regard to the parameters of the friction characteristic. Either of the blades is discretized by FEM using beam elements and continuously distributed weight is concentrated in nodal points. The friction in central contact points between blade shrouds and the friction element is approximated by a continuous function depending on slip velocities of the shrouds relative to the friction element. Considered friction characteristic respects the micro-slip phase at the very low slip velocities and the macro-slip (full-slip) phase at the higher slip velocities. The values of the friction characteristic parameters are identified by comparison of the numerical simulations of a transient vibration with experiments used in IT AS CR. and Obsahuje seznam literatury
Gaits is one of the splendid functions, which concerns every human being. The standard gait is perceived as precisely controlled activities, based on the periodically coordinated, recurrent leg and trunk (torso) movements, which provide the relocation of the human body from one place to another with the minimal waste energy (Gage J.R., DeLuca P.A., Renshaw T.S. - gait definition) [2]. Different types of diseases cause the changes in gait pattern of the parients. The patients, who have the certain diseases since they were born and the acquired diseases have different deviations from the gait pattern. The conclusion is that there is no universal gait pattern.
The gait of the patients with implants differs from the gait pattern and in this case it depends on the implants type. Analysis and estimation of the gait of the people who have implants is problematic, that is why the paper presents the research connected with the gait diagnostics for people with implants.
The analysis of in situ measurements of velocity distribution in the floodplain of the lowland river has been carried out. The survey area was located on a bypass channel of the Warta River (West of Poland) which is filled with water only in case of flood waves. The floodplain is covered by grassland and reed marsh habitats. The velocity measurements were performed with an acoustic Doppler current profiler (ADCP) in a cross-section with a bed reinforced with concrete slabs. The measured velocities have reflected the differentiated impact of various vegetation types on the loss of water flow energy. The statistical analyses have proven a relationship between the local velocities and the type of plant communities.
In the paper an analysis of the influence of physical conditions inside the interelectrode gap (IEG) on the workpiece (WP) shape evolution has been presented. This problem has been solved on the basis of a two-dimensional model of an electrolyte and hydrogen mixture flow through the interelectrode gap (IEG). There has also been demonstrated general mathematical modeling algorithm as well as a numerical calculation scheme. and Obsahuje seznam literatury
The potential role of intestinal intraepithelial lymphocytes (i-IELs) in the generation of host protective immunity after helminth infection was investigated using the Trichinella spiralis (Owen, 1835)/mouse model. In this study we found a significant rise of TCRyô i-IELs (P < 0.001) concurrent with the jejunal goblet cells (GC) hyperplasia in T. spiralis-infected C57BL mice on day 4 p.i. However, no direct relationship between the kinetics of the increase in TCRy5+ i-IELs and T, spiralis expulsion was observed in infected mice. Taken together, these results implicate that γδ i-IELs probably perform a unique functions related to the regulation of the CiC proliferation accompanying T. spiralis gut infection. As is known, these TCRyS* i-IELs may release mediators or growth factors that in turn influence GC differentiation. With the use of dexamethason (DEX), a potent anti-inflammatory agent which also induces apoplotic ceil death in i-IELs, wc have confirmed that the expulsion of T. spiralis from the mouse gut is accompanied by an inflammatory response. Indeed, the GC are clearly involved in these phenomena, apparently under the regulation by TCRy8+ i-lEL-mediated responses, since DEX abrogated GC proliferation in T. spiralis-infected C57BL mice and subsequently augmented adult worm burden. Our data also show that the rejection of adult worms starts concurrently with a significant increase in TCRaß* and CDS* i-IELs (P < 0.05 and P < 0.01, respectively), namely by day 7 p.i. At the same time, CD4* cells significantly decreased (P < 0.05) in the intestinal epithelium of T. spira/ir-infected, ví uninfected mice. These results may indicate that the TCRaß4 and CDS* i-IELs act as effectors of anti-7’, spiralis defence reactions. The implications of these findings for the potential role of intestinal intraepithélial CD8 and TCRaß' cells in the pathogenesis of the intestinal lesions during T. spiralis gut infection are discussed.
The sequences of 10 conservative regions (CR) of minicircles of 6 selected isolates of freshwater fish try-panosomes have typical organization of this region with high degree of sequence conservation. The comparison with CRs of other trypanosomatids showed that freshwater fish trypanosomes represent a compact separate group within the genus Trypanosoma. The alignment of all sequences obtained revealed, however, the existence of 2 types of CRs in sequenced minicirclcs, with the differences concentrated in a short region. Taxonomic consequences of these results arc discussed.