Project of Regular Intercontinental Line Prague - Chicago

Bakalářská práce se zabývá projektem pravidelné mezikontinentální linky Praha – Chicago. V práci je popsána historie dálkových letů provozovaných z Československa a České republiky v minulosti, plánování a provedení dálkového letu, identifikace vhodného typu letounu a rámcové ekonomické zhodnocení projektovaného letu. K naplánování trasy dálkového letu byla využita veřejně dostupná aplikace SimBrief. Hlavní části bakalářské práce je matematický výpočet pomocí metody váženého součtu, který určil optimální letoun pro let na trase Praha – Chicago. Poslední kapitola se zabývá ekonomickým zhodnocením projektovaného letu, kde jsou započítány veškeré poplatky související s letem.The bachelor's thesis deals with the project of a regular intercontinental line Prague - Chicago. The work describes the history of long-haul flights operated from Czechoslovakia and the Czech Republic in the past, planning and execution of long-haul flights, identification of a suitable type of aircraft and general economic evaluation of the projected flight. The publicly available SimBrief application was used to plan a long-haul flight route. The main part of the bachelor's thesis is a mathematical calculation using the weighted sum method, which determined the optimal aircraft for the flight on the route Prague - Chicago. The last chapter deals with the economic evaluation of the designed flight, which includes all fees related to the flight.342 - Institut dopravyvelmi dobř

Ecosystem transpiration and evaporation: Insights from three water flux partitioning methods across FLUXNET sites

We apply and compare three widely applicable methods for estimating ecosystem transpiration (T) from eddy covariance (EC) data across 251 FLUXNET sites globally. All three methods are based on the coupled water and carbon relationship, but they differ in assumptions and parameterizations. Intercomparison of the three daily T estimates shows high correlation among methods (R between .89 and .94), but a spread in magnitudes of T/ET (evapotranspiration) from 45% to 77%. When compared at six sites with concurrent EC and sap flow measurements, all three EC‐based T estimates show higher correlation to sap flow‐based T than EC‐based ET. The partitioning methods show expected tendencies of T/ET increasing with dryness (vapor pressure deficit and days since rain) and with leaf area index (LAI). Analysis of 140 sites with high‐quality estimates for at least two continuous years shows that T/ET variability was 1.6 times higher across sites than across years. Spatial variability of T/ET was primarily driven by vegetation and soil characteristics (e.g., crop or grass designation, minimum annual LAI, soil coarse fragment volume) rather than climatic variables such as mean/standard deviation of temperature or precipitation. Overall, T and T/ET patterns are plausible and qualitatively consistent among the different water flux partitioning methods implying a significant advance made for estimating and understanding T globally, while the magnitudes remain uncertain. Our results represent the first extensive EC data‐based estimates of ecosystem T permitting a data‐driven perspective on the role of plants’ water use for global water and carbon cycling in a changing climate

Akciová společnost s působením v oblasti obchodu

PrezenčníNeuvedenoNeuveden

Stanovení vlivu svařovacích parametrů na šířku tepelně ovlivněné oblasti při svařování oceli StE 445.7TM

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Fakulta strojní. Katedra (345) mechanické technologi

Individual variability in habitat selection by aquatic insects is driven by taxonomy rather than specialisation

Abstract Habitat selection, the choice of a habitat based on its perceived quality, is a key mechanism structuring freshwater communities. To date, individual variability in habitat selection has been neglected, and specialisation has never been considered in this type of studies. We examined the individual differences in the habitat selection of backswimmers (Notonectidae) and diving beetles (Dytiscidae). From each family, we selected one habitat generalist able to coexist with fish (Notonecta glauca, Dytiscus marginalis), and one species specialised to fishless habitats (Notonecta obliqua, Acilius sulcatus). We performed a mesocosm experiment quantifying the consistency in individuals’ decisions in response to fish and vegetation structure, in relation to sex and specialisation. Neither the overall pattern of preferences nor consistency in individuals’ decisions differed between specialists and generalists or between the sexes, but both were consistent within families. At the population level, backswimmers preferred fishless pools with submersed and floating macrophytes, while diving beetles showed no clear preferences. Individual decisions of backswimmers were consistent and likely driven by conspecific/heterospecific attraction. In diving beetles, individual decisions were primarily density-dependent. Our results reinforce the significance of habitat selectivity for aquatic community assembly, while suggesting a range of mechanisms driving variability in individual behaviour

Line plots showing differences in mean spine lengths (L9, L8, D8–D5) across predator treatments (F = fish, I = invertebrate, M = mixed, C = control).

<p>Length is expressed as spine length/head width. Points and lines represent means and standard errors, respectively.</p

Test statistics from linear mixed-effect models (LMMs) showing spine length differences across predator treatments (fish, invertebrate, mixed) compared with control.

<p>Test statistics from linear mixed-effect models (LMMs) showing spine length differences across predator treatments (fish, invertebrate, mixed) compared with control.</p

Measurements of larval <i>Sympetrum depressiusculum</i> after induction experiment.

<p><b>(A)</b> head width; <b>(B)</b> dorsal and <b>(C)</b> lateral spines were measured from the base of each segment to the tip of the spine along the interior margin of the spine.</p

Principal coordinates analysis (PCoA) plot showing significant dissimilarities (<i>P</i> = 0.027) between predator treatments (fish, invertebrate, mixed, control) in spine length.

<p>Each point represents the position of an individual larva in the ordination space based on the measurements of all six spines. Length is expressed as spine length/head width.</p

Data from: Avoiding erroneous citations in ecological research: read before you apply

The Shannon–Wiener index is a popular nonparametric metric widely used in ecological research as a measure of species diversity. We used the Web of Science database to examine cases where papers published from 1990 to 2015 mislabelled this index. We provide detailed insights into causes potentially affecting use of the wrong name ‘Weaver’ instead of the correct ‘Wiener’. Basic science serves as a fundamental information source for applied research, so we emphasize the effect of the type of research (applied or basic) on the incidence of the error. Biological research, especially applied studies, increasingly uses indices, even though some researchers have strongly criticized their use. Applied research papers had a higher frequency of the wrong index name than did basic research papers. The mislabeling frequency decreased in both categories over the 25-year period, although the decrease lagged in applied research. Moreover, the index use and mistake proportion differed by region and authors’ countries of origin. Our study also provides insight into citation culture, and results suggest that almost 50% of authors have not actually read their cited sources. Applied research scientists in particular should be more cautious during manuscript preparation, carefully select sources from basic research, and read theoretical background articles before they apply the theories to their research. Moreover, theoretical ecologists should liaise with applied researchers and present their research for the broader scientific community. Researchers should point out known, often-repeated errors and phenomena not only in specialized books and journals but also in widely used and fundamental literature