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1882. A redescription of Trichosurolaelaps dixous Domrow, 1972 (Acari: Laelapidae), from Trichosurus cunninghami (Marsupialia: Phalangeridae) from southern Australia
- Creator:
- Hufschmid, Jasmin, Beveridge, Ian, Handasyde, Kathrine Ann, and Spratt, David Michael
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Trichosurolaelaps dixous, Trichosurolaelaps crassipes, Trichosurus cunninghami, Trichosurus vulpecula, ectoparasites, Acari, and Laelapidae
- Language:
- English
- Description:
- The adults of Trichosurolaelaps dixous Domrow, 1972 are redescribed from a population of Trichosurus cunninghami Lindenmayer, Dubach et Viggers, 2002 in south-eastern Australia. The nymphal stages are described for the first time. Morphologically, T. dixous is similar to Trichosurolaelaps crassipes Womersley, 1956. Morphological differences between the pre-female deutonymphs and adult females of the two mite species are the presence of a single large ventral spur on tibia I of T. dixous. Males of T. dixous could not be distinguished from T. crassipes morphologically and the idiosomal length of male T. dixous was variable (475-683 μm). Protonymphs of the two mite species differed only in size, with that of T. dixous being larger. Although T. crassipes was prevalent in a sympatric population of Trichosurus vulpecula and has been reported from other populations of T. cunninghami in southern Australia, it was never recovered from the population of T. cunninghami studied.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1883. A reference model for the atmosphere of Titan
- Creator:
- Petropoulos, B. and Georgakilas, A. A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- space research, physical parameters, and atmosphere of Titan
- Language:
- Czech
- Description:
- We have computed the following physical parameters for the atmosphere of Titan, usinge Voyager´s measurements: 1) Temperature, 2) Pressure, 3) Density, 4 Speed of sound, 5) Density scale, 6) Number density, 7) Mean free path, 8) Viscosity, 9) Pressure scale, 10) Mean particle velocity, 11) Mean collisional frequency, 12) Columnar mass.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1884. A refinement of the radial Pohozaev identity
- Creator:
- Catrina, Florin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Green's function, positive solutions, and supercritical nonlinearity
- Language:
- English
- Description:
- In this article we produce a refined version of the classical Pohozaev identity in the radial setting. The refined identity is then compared to the original, and possible applications are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1885. A regional comparative analysis of empirical and theoretical flood peak-volume relationships
- Creator:
- Szolgay, Ján, Gaál, Ladislav, Bacigál, Tomáš, Kohnová, Silvia, Hlavčová, Kamila, Výleta, Roman, Parajka, Juraj, and Blöschl, Günter
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- flood types, regionalisation, flood peaks, flood volumes; copulas, copulas, goodness-of-fit, and comparative hydrology
- Language:
- Slovak
- Description:
- 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.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1886. A reinvestigation of spermiogenesis in Amphilina foliacea (Platyhelminthes: Amphilinidea)
- Creator:
- Bruňanská, Magdaléna, Poddubnaya, Larisa G., and Xylander, Willi E. R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- ultrastructure, testes, spermiogenesis, Amphilina foliacea, Amphilinidea, Cestoda, and Platyhelminthes
- Language:
- English
- Description:
- Spermiogenesis in the amphilinidean cestode Amphilina foliacea (Rudolphi, 1819) was examined using transmission electron microscopy. The orthogonal development of the two flagella is followed by a flagellar rotation and their proximodistal fusion with the median cytoplasmic process. This process is accompanied by extension of both the mitochondrion and nucleus into the median cytoplasmic process. The two pairs of electron-dense attachment zones mark the lines where the proximodistal fusion of the median cytoplasmic process with the two flagella takes place. The intercentriolar body, previously undetermined in A. foliacea, is composed of three electron-dense and two electron-lucent plates. Also new for this species is the finding of electron-dense material in the apical region of the differentiation zone at the early stage of spermiogenesis, and the fact that two arching membranes appear at the base of the differentiation zone only when the two flagella rotate towards the median cytoplasmic process. The present data add more evidence for a close relationship between the Amphilinidea and the Eucestoda.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1887. A related-key attack on iterated chaotic ciphers
- Creator:
- Yang, Yang and Jin, Chenhui
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chaotic cipher, related-key attack, ZLL chaotic cipher, divide-and-conquer attack, and known plaintexts attack
- Language:
- English
- Description:
- In this paper, we present a new type of attack on iterated chaotic ciphers using related keys. Based on the fact that a chaotic sequence is not sensitive to the less significant bits of initial conditions and parameters, a divide-and-conquer attack on iterated chaotic ciphers was presented by us before, which significantly reduces the computing complexity of attacks. However, if the information leaked is significant according to the distribution of the coincidence degrees, a measure for the information leakage of chaotic ciphers, or the size of the key is large, then it is difficult for the divide-and-conquer attack to reduce its computing complexity into a realizable level. The related-key attack we present in this paper simultaneously uses the information leaked from different chaotic sequences generated by related keys and combines the ideas of linear cryptanalysis and divide-and-conquer attack together, hence greatly enhances the efficiency of divide-and-conquer attack. As an example, we test the related-key attack on the ZLL chaotic cipher with a 64-bit key on a Pentium IV 2.5 GHz PC, which takes only 8 minutes and 45 seconds to recover all bits of the key successfully.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1888. A relevance vector machine with rough set theory model in analyzing the life cycle of new economic firms
- Creator:
- Hsu, Ming-Fu, Ping-Feng, Pai, and Chung, Wei-Shih
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Corporate life cycle, rough set theory, relevance vector machine, and transparency and disclosure
- Language:
- English
- Description:
- The subprime mortgage crisis and subsequent financial tsunami have raised considerable concerns about financial risk management and evaluation. This is nowhere more apparent than in new economic firms (NEFs) with large economic targets and heavy R&D expenses, such as firms in the electronics industries. With its potential for extreme growth and superior profitability, the electronic industries in Taiwan have been in the financial stock market spotlight. Recently, the relevance vector machine (RVM) was reported to have considerably less computation complexity than support vector machines (SVM) models, since it uses fewer kernel functions. Another emerging technique is rough set theory (RST), which derives rules from data. Based on the corporation life cycle theory (CLC), this study developed a relevance vector machine with rough set theory (RVMRS) to predict the status of a corporation in the decline stage. To demonstrate the performance of the designed RVMRS model, the study used electronic industries data from the Taiwan Economic Journal data bank, Taiwan Security Exchange, and Securities and Futures Institute in Taiwan. Experimental results revealed that the presented RVMRS model can predict the decline stage in a firm's life cycle with satisfactory accuracy, and generate rules for investors, managers, bankers and regulators that enable them to make suitable judgments. In addition, this study proved that the transparency and information disclosure index (TDI) is crucial to predicting the financial decline of corporations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1889. A remark on $k$-systems in groups
- Creator:
- Parmenter, M. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- math and $k$-systems
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1890. A remark on branch weights in countable trees
- Creator:
- Zelinka, Bohdan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- branch weight, branch weight centroid, tree; path, and degree of a vertex
- Language:
- English
- Description:
- Let T be a tree, let u be its vertex. The branch weight b(u) of u is the maximum number of vertices of a branch of T at u. The set of vertices u of T in which b(u) attains its minimum is the branch weight centroid B(T) of T. For finite trees the present author proved that B(T) coincides with the median of T, therefore it consists of one vertex or of two adjacent vertices. In this paper we show that for infinite countable trees the situation is quite different.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public