Longwave radiation, as part of the radiation balance, is one of the factors needed to estimate potential evapotranspiration (PET). Since the longwave radiation balance is rarely measured, many computational methods have been designed. In this study, we report on the difference between the observed longwave radiation balance and modelling results obtained using the two main procedures outlined in FAO24 (relying on the measured sunshine duration) and FAO56 (based on the measured solar radiation) manuals. The performance of these equations was evaluated in the April–October period over eight years at the Liz experimental catchment and grass surface in the Bohemian Forest (Czech Republic). The coefficients of both methods, which describe the influence of cloudiness factor and atmospheric emissivity of the air, were calibrated. The Penman-Monteith method was used to calculate the PET. The use of default coefficient values gave errors of 40–100 mm (FAO56) and 0–20 mm (FAO24) for the seasonal PET estimates (the PET was usually overestimated). Parameter calibration decreased the FAO56 error to less than 20 mm per season (FAO24 remained unaffected by the calibration). The FAO56 approach with calibrated coefficients proved to be more suitable for estimation of the longwave radiation balance.
The use of environmentally-friendly materials in hydraulic engineering (e.g. the stone lining of weirs at levees) calls for the more accurate estimation of the discharge coefficient for broad-crested weirs with a rough crest surface. However, in the available literature sources the discharge coefficient of broad-crested weirs is usually expressed for a smooth crest. The authors of this paper have summarized the theoretical knowledge related to the effect of weir crest surface roughness on the discharge coefficient. The method of determination of the head-discharge relation for broad-crested weirs with a rough crest surface is proposed based on known discharge coefficient values for smooth surfaces and on the roughness parameters of the weir. For selected scenarios the theoretical results were compared with experimental research carried out at the Laboratory of Water Management Research, Faculty of Civil Engineering (FCE), Brno University of Technology (BUT). and Používání přírodě blízkých materiálů ve vodním hospodářství (např. kamenná opevnění povrchu přelivů v ochranných hrázích) vyvolává požadavek přesnějšího stanovení součinitele průtoku pro přelivy se širokou a hydraulicky drsnou korunou. V dostupných literárních pramenech je součinitel průtoku přelivů se širokou korunou obvykle vyjádřen pouze pro hladký povrch koruny přelivu. Autoři článku shrnuli teoretické poznatky týkající se vlivu drsnosti povrchu koruny přelivu na součinitel průtoku a navrhli metodu pro stanovení způsobu hydraulického výpočtu konzumční křivky přepadu přes přeliv se širokou a drsnou korunou. Postup vychází ze znalosti součinitele průtoku přelivu s hladkou korunou a charakteristik drsnosti. Pro vybrané scénáře byly teoreticky vypočítané hodnoty porovnány s výsledky experimentálního výzkumu uskutečněného v Laboratoři vodohospodářského výzkumu Ústavu vodních staveb, Fakulty stavební, Vysokého učení technického v Brně.
In normal practice, during the estimation of reservoir storage uncertainties affecting the values of mean monthly discharge series are not normally considered, and usually no estimates of these are known. Therefore, the question arises as to whether the results of the estimation of the capacity of storage reservoirs may be affected by uncertainties in the discharge series. The aim of this article is the suggestion of a possible approach to estimating the level of uncertainties affecting the elements of mean monthly discharge series. These discharge series are subsequently integrated into water reservoir storage capacity calculations, and the significance of the proposed approach is explored. and Nejistoty členů řad průměrných měsíčních průtoků nejsou v běžné praxi udávány, není ani znám odhad jejích velikostí. Otázkou rovněž je, zda nejistotami zatížené průtokové řady mohou ovlivnit výsledky vodohospodářského řešení zásobní funkce vodní nádrže. Cílem článku je naznačení možného postupu odhadu míry nejistot zatěžujících členy průtokové řady průměrných měsíčních průtoků a následné začlenění uvedené řady do výpočtů zásobního objemu vodní nádrže a posouzení významu uvedeného postupu.
River runoff and sediment transport are two related random hydrologic variables. The traditional statistical analysis method usually requires those two variables to be linearly correlated, and also have an identical marginal distribution. Therefore, it is difficult to know exactly the characteristics of the runoff and sediment in reality. For this reason, copulas are applied to construct the joint probability distribution of runoff and sediment in this article. The risk of synchronous-asynchronous encounter probability of annual rich-poor runoff and sediment is also studied. At last, the characteristics of annual runoff and sediment with multi-time scales in its joint probability distribution space are simulated by empirical mode decomposition method. The results show that the copula function can simulate the joint probability distribution of runoff and sediment of Huaxia hydrological station in Weihe River well, and that such joint probability distribution has very complex change characteristics at time scales.
This paper develops an account of judge-dependence, conceived of as a generalization of the better known notion of response-dependence. It then solves a number of problems for the view that aesthetic judgements are judge-dependent in this sense. Finally, a parallel case for the judge-dependence of moral judgement is assessed.
In slurry transport of settling slurries in Newtonian fluids, it is often stated that one should apply a line speed above a critical velocity, because blow this critical velocity there is the danger of plugging the line. There are many definitions and names for this critical velocity. It is referred to as the velocity where a bed starts sliding or the velocity above which there is no stationary bed or sliding bed. Others use the velocity where the hydraulic gradient is at a minimum, because of the minimum energy consumption. Most models from literature are one term one equation models, based on the idea that the critical velocity can be explained that way. Here the following definition is used: The critical velocity is the line speed below which there may be either a stationary bed or a sliding bed, depending on the particle diameter and the pipe diameter, but above which no bed (stationary or sliding) exists, the Limit Deposit Velocity (LDV). The way of determining the LDV depends on the particle size, where 5 regions are distinguished. These regions for sand and gravel are roughly; very small particles up to 0.014-0.040 mm (d < δv), small particles from δv-0.2 mm, medium particles in a transition region from 0.2-2.00 mm, large particles > 2 mm and very large particles > 0.015·Dp. The lower limit of the LDV is the transition between a sliding bed and heterogeneous transport. The new model is partly based on physics and correlates well with experiments from literature.
While prototypical uses of slurs express contempt for targets, some reclaimed uses are associated with positive evaluations. This practice may raise concerns. I anticipate this criticism in what I dub the Warrant Argument (WA) and then defend the legitimacy of this kind of reclamation. For the WA, standard pejorative uses of slurs are problematic for assuming unwarranted connections between descriptive properties (e.g., being gay) and value judgements (e.g., being worthy of contempt). When reclaimed uses of slurs express a positive evaluation of their targets—the WA goes—reclamation fails to challenge the unwarranted link between descriptive properties and value judgements, and merely reverses the evaluation polarity from negative to positive. So, the WA concludes, reclaimed uses of slurs evaluating targets positively for belonging to a certain group make a similar moral error as derogatory uses of slurs (sections 2-3). The WA could lead us to condemn reclamation. To resist this conclusion, I draw a parallel with affirmative action, arguing that it can be morally permissible to balance an existing form of injustice by temporarily introducing a countervailing mechanism that prima facie seems to violate the norm of equality: even if the WA were right, it wouldn’t constitute an argument against the moral permissibility of reclamation in the case of most slurs (section 4). This line of argument in defense of pride reclamation may also serve to debunk the myths of reverse racism and reverse sexism (section 5).
Personites are shorter-lived, person-like things that extend across part of a person’s life. Their existence follows from the standard perdurance view of persons. Johnston argues that it has bizarre moral consequences. For example, it renders morally problematic spending time learning a difficult language in anticipation of going abroad. The crucial thought is that if persons have moral status so do personites. Johnston argues for this claim. Kaiserman responds, on behalf of stage theory, that this only works on a perdurantist account. This is a conservative response to the problem. It seeks to show that retaining the ontology of perdurantism one can resolve the difficulty by a semantic change. I show that the personite problem can be reworked as an argument against stage theorists. The stage theorist can respond by rejecting an assumption of the reasoning. But if it is acceptable for him to do so the perdurantist can reject this assumption too, which is enough by itself to block Johnston’s argument. Thus, for all it helps with the personite problem, stage theorists might as well be perdurantists.
In the article, we present analyses and findings which add precision to the role of intentions and the relation between effects in attributing the intentionality of causing a side effect. Our research supplements and modifies numerous findings regarding the appearance of the so-called Knobe effect. The experiments and analyses show that the very originality of the story used by Knobe and the relationship between the evaluative properties of the main effect and the side effect results in an asymmetry of responses and contributes to the occurrence of the side-effect effect. Because of this, we reject the thesis that the mode of attitude of the agent to the caused side effect or that the social expectation of this attitude determine the attribution of the intentionality of the caused effect. On the contrary, we defend the thesis that it is the relationship between the evaluative properties of the main effect and those of the side effect, as well as the impact of a side effect on the main effect, that significantly influence the attribution of intentionality in causing a side effect.