One of the most important problems faced in hydrology is the estimation of flood magnitudes and frequencies in ungauged basins. Hydrological regionalisation is used to transfer information from gauged watersheds to ungauged watersheds. However, to obtain reliable results, the watersheds involved must have a similar hydrological behaviour. In this study, two different clustering approaches are used and compared to identify the hydrologically homogeneous regions. Fuzzy C-Means algorithm (FCM), which is widely used for regionalisation studies, needs the calculation of cluster validity indices in order to determine the optimal number of clusters. Fuzzy Minimals algorithm (FM), which presents an advantage compared with others fuzzy clustering algorithms, does not need to know a priori the number of clusters, so cluster validity indices are not used. Regional homogeneity test based on L-moments approach is used to check homogeneity of regions identified by both cluster analysis approaches. The validation of the FM algorithm in deriving homogeneous regions for flood frequency analysis is illustrated through its application to data from the watersheds in Alto Genil (South Spain). According to the results, FM algorithm is recommended for identifying the hydrologically homogeneous regions for regional frequency analysis.
Fishway design not only takes into account the swimming abilities of target fishes, but also considers the hydrodynamic characteristics within the fishway. In this study, the flow fields of one vertical-slot fishway (i.e. VSF), five T-shape fishways (i.e. TSF-1~TSF-5) and two H-shape fishways (i.e. HSF-1 and HSF-2) are numerically simulated by solving the three-dimensional Reynolds-averaged Navier-Stokes equations and the K-Omega-SST turbulence model. The numerical results clearly indicate that the hydrodynamic properties of HSF-2 are overall superior to the remaining seven cases, in terms of the time-averaged flow pattern, the time-averaged velocity magnitude, the depth-mean timeaveraged velocity magnitude along the vertical-slot section, the volume percentages of the time-averaged velocity magnitude less than some critical values, and the distribution of the time-averaged turbulent kinetic energy. Therefore, HSF-2 is more friendly for fishes with relatively smaller sizes and weaker swimming capacities to transfer upstream. The novel HSF-2 is firstly proposed in this paper, and it is naturally designed during the process of improving the flow regime. Furthermore, the generalizability of the superiority of HSF-2 over VSF and the original T-shape fishway (i.e. TSF-1) has been exhibited with the aid of the numerical results of four operating conditions (i.e. Q = 400 L/s, 600 L/s, 800 L/s and 1000 L/s).
In passing remarks, some commentators have noted that for Nagel, physicalism is true. It has even been argued that Nagel seeks to find the best path to follow to achieve future physicalism. I advance these observations by adding that for Nagel, we should discuss the consciousness problem not in terms of physical and mental issues but in terms of our desire to include consciousness in an objective/scientific account, and we can achieve this only by revising our self-conception, i.e., folk psychology, to develop a more detached view of experience. Through the project of objective phenomenology, Nagel aims to achieve some sort of objective, detached, and scientific explanation of the subjective nature of experience. This project seeks to make the truth of physicalism intelligible and consciousness more amenable to scientific study, potentially raising an even broader concept than the one physicalism originally proposes.
Steady two-dimensional natural convection taking place in a rectangular cavity, partially filled with an isotropic porous material, has been investigated numerically using an ADI method. It is assumed that one of the vertical walls of the cavity has a ramped temperature distribution. The vorticity-stream function formulation has been used to solve the set of nonlinear partial differential equations governing the flows in the clear region and the adjoining porous region. The effects of Darcy number and Rayleigh number have been discussed in detail.
Dead-end pores are usually present in natural porous media especially in consolidated sandstone and limestone rocks. However, the presence of the dead-end pores is usually ignored. Then, the influences of the dead end pores to the flow system are also neglected. In this paper, pressure changes for the periods of transient and steady state of the dead-end pores are studied using lattice gas automata model. A simulation result is compared with the past works. They show that the model is viable to perform simulation of deadend pore pressure. Some parameters such as pressure distribution and size of neck and body of the dead-end pores are varied to examine their effects. We found that the parameters affect the rate of pressure change during transient period. In addition, the parameters also affect the pressure fluctuation during steady state period. The dead-end pores have function either as source or sink in the transient period depend on initial and injection pressures. During steady state period, the dead-end pores behave both as source and sink since the pressure in the pores fluctuates around an equilibrium pressure between the pressure of dead-end pore and that of main channel at the neck position of dead-end pore. and Takzvané mŕtve póry (neprietočné póry) sa často nachádzajú v prírodných pórovitých prostrediach, predovšetkým v skonsolidovaných pieskovcoch a vo vápencoch. Obvykle sa ich existencii nevenuje pozornosť. Pozornosť sa nevenuje ani ich vplyvu na prúdenie v tomto systéme. V tomto príspevku sú študované zmeny tlaku v mŕtvych póroch počas neustáleného a ustáleného prúdenia s použitím ''lattice gas automata'' modelu. Výsledky simulácie sme porovnali s predchádzajúcimi prácami. Výsledky naznačujú, že tento model je vhodný na simuláciu zmien tlakov v mŕtvych póroch. Vplyv niektorých parametrov, ako je rozdelenie tlakov a tvary ''krčkov'' (spojovacích pórov) ako aj mŕtvych pórov boli menené tak, aby sme mohli pozorovať ich vplyv na prúdenie. Zistili sme, že tieto parametre ovplyvňujú rýchlosť zmien tlakov počas neustáleného prúdenia. Navyše sme zistili, že tieto parametre ovplyvňujú fluktuáciu tlakov počas ustáleného prúdenia. Mŕtve póry môžu počas neustáleného prúdenia fungovať ako zdroje alebo odbery, v závislosti od počiatočného, alebo ''plniaceho'' tlaku. Počas ústáleného prúdenia sa mŕtve póry správajú ako zdroje alebo aj odbery, pretože tlak v póroch fluktuuje okolo rovnovážneho tlaku medzi tlakom v mŕtvych póroch a hlavným kanálom v závislosti od vlastností ''krčku'' mŕtveho póru.
There are nine antirealist explanations of the success of science in the literature. I raise difficulties against all of them except the latest one, and then construct a pessimistic induction that the latest one will turn out to be problematic because its eight forerunners turned out to be problematic. This pessimistic induction is on a par with the traditional pessimistic induction that successful present scientific theories will be revealed to be false because successful past scientific theories were revealed to be false., V literatuře existuje devět antirealistických vysvětlení úspěchu vědy. Vyvolávám obtíže proti všem, s výjimkou posledního, a pak buduji pesimistickou indukci, že poslední z nich bude problematická, protože osm předchůdců se ukázalo jako problematické. Tato pesimistická indukce je na stejné úrovni s tradiční pesimistickou indukcí, že úspěšné současné vědecké teorie budou odhaleny jako nepravdivé, protože úspěšné minulé vědecké teorie byly odhaleny jako nepravdivé., and Seungbae Park
Those who argue that dispositional explanations are genuine explanations usually construe them as causal explanations. There are several well-known arguments against the causal efficacy of dispositions, but there are as well demonstrations that on some minimal conditions, dispositions could be viewed as causally relevant to the effects which they are taken to explain. Although the latter position is generally tenable, it may be shown that in some important cases it is not a good idea to commit to a causal construal of dispositional explanations. The argument goes as follows: (1) Dispositional explanations are valued for certain specific extra-inferences which they allow us to draw; (2) The causal construal of dispositional explanations can account for some of these extra-inferences only on the assumption that the disposition is a common cause of its manifestations; (3) However, under certain circumstances, the common cause assumption is refuted on theoretical or empirical grounds; Therefore, (4) under certain circumstances, the causal construal of dispositional explanations cannot account for what these explanations are valued for. The latter conclusion is a reason to argue that in some cases at least, the causal construal of dispositional explanations should be avoided., Ti, kteří tvrdí, že dispoziční vysvětlení jsou skutečná vysvětlení, je obvykle považují za kauzální vysvětlení. Existuje několik dobře známých argumentů proti kauzální účinnosti dispozic, ale jsou zde také demonstrace, že za určitých minimálních podmínek lze dispozice považovat za kauzálně relevantní vzhledem k účinkům, které mají být vysvětleny. I když je tato pozice obecně udržitelná, může být prokázáno, že v některých důležitých případech není dobré zavázat se k příčinnému konstruktivnímu vysvětlení. Argument jde následovně: (1) Dispoziční vysvětlení jsou oceňována pro určité specifické extra-závěry, které nám umožňují kreslit; (2) Kauzální konstrukční dispoziční vysvětlení může vysvětlit některé z těchto extra-dedukcí pouze za předpokladu, že dispozice je společnou příčinou jejích projevů; (3) Za určitých okolností je však předpoklad společné příčiny vyvrácen z teoretických nebo empirických důvodů; Proto (4) za určitých okolností nemůže kauzální konstrukční vysvětlení vysvětlení vysvětlit, za co jsou tato vysvětlení oceňována. Tento závěr je důvodem pro tvrzení, že v některých případech je třeba se vyhnout kauzálnímu konstrukčnímu vykládání vysvětlení. kauzální konstruktivní vysvětlení nemůže vysvětlit, za co jsou tato vysvětlení oceňována. Tento závěr je důvodem pro tvrzení, že v některých případech je třeba se vyhnout kauzálnímu konstrukčnímu vykládání vysvětlení. kauzální konstruktivní vysvětlení nemůže vysvětlit, za co jsou tato vysvětlení oceňována. Tento závěr je důvodem pro tvrzení, že v některých případech je třeba se vyhnout kauzálnímu konstrukčnímu vykládání vysvětlení., and Lilia Gurova
This paper analyses the bivariate relationship between flood peaks and corresponding flood event volumes modelled by empirical and theoretical copulas in a regional context, with a focus on flood generation processes in general, the regional differentiation of these and the effect of the sample size on reliable discrimination among models. A total of 72 catchments in North-West of Austria are analysed for the period 1976-2007. From the hourly runoff data set, 25 697 flood events were isolated and assigned to one of three flood process types: synoptic floods (including long- and short-rain floods), flash floods or snowmelt floods (both rain-on-snow and snowmelt floods). The first step of the analysis examines whether the empirical peak-volume copulas of different flood process types are regionally statistically distinguishable, separately for each catchment and the role of the sample size on the strength of the statements. The results indicate that the empirical copulas of flash floods tend to be different from those of the synoptic and snowmelt floods. The second step examines how similar are the empirical flood peak-volume copulas between catchments for a given flood type across the region. Empirical copulas of synoptic floods are the least similar between the catchments, however with the decrease of the sample size the difference between the performances of the process types becomes small. The third step examines the goodness-of-fit of different commonly used copula types to the data samples that represent the annual maxima of flood peaks and the respective volumes both regardless of flood generating processes (the traditional engineering approach) and also considering the three process-based classes. Extreme value copulas (Galambos, Gumbel and Hüsler-Reiss) show the best performance both for synoptic and flash floods, while the Frank copula shows the best performance for snowmelt floods. It is concluded that there is merit in treating flood types separately when analysing and estimating flood peak-volume dependence copulas; however, even the enlarged dataset gained by the process-based analysis in this study does not give sufficient information for a reliable model choice for multivariate statistical analysis of flood peaks and volumes.
Using ideas from John Searle, Roy Harris, Michael Reddy, and Nelson Goodman, I argue that texts, such as they are commonly conceived, lack brute existence. The common idea of texts is a conceptual construction which is useful in practical everyday contexts but not in serious theorizing, where it creates illusions and contradictions. One of these illusions is the idea of an objective textual meaning, a meaning which is ''in the text'': what we actually have in the way of textual meaning are the ideas of various persons – authors, readers, and commentators – about the meaning of the text. When applied to fictional characters, this way of viewing things explains why it makes sense to regard fictional characters as being created and as lacking brute existence., Použitím nápadů od Johna Searleho, Roy Harris, Michaela Reddyho a Nelsona Goodmana, tvrdím, že texty, tak jak jsou běžně koncipovány, postrádají hrubou existenci. Společná myšlenka textů je koncepční konstrukce, která je užitečná v praktických každodenních kontextech, ale ne ve vážném teoretizování, kde vytváří iluze a protiklady. Jednou z těchto iluzí je myšlenka objektivního textuálního významu, významu, který je "v textu": to, co vlastně máme ve způsobu textuálního významu, jsou myšlenky různých osob - autorů, čtenářů a komentátorů - o významu textu. Při použití na fiktivní postavy vysvětluje tento způsob prohlížení věci, proč má smysl považovat fiktivní postavy za vytvořené a chybějící hrubou existenci., and Anders Pettersson
The contribution focuses on the design of a control algorithm aimed at the operative control of runoff water from a reservoir during flood situations. Management is based on the stochastically specified forecast of water inflow into the reservoir. From a mathematical perspective, the solved task presents the control of a dynamic system whose predicted hydrological input (water inflow) is characterised by significant uncertainty. The algorithm uses a combination of simulation model data, in which the position of the bottom outlets is sought via nonlinear optimisation methods, and artificial intelligence methods (adaptation and fuzzy model). The task is written in the technical computing language MATLAB using the Fuzzy Logic Toolbox.