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1542. A Miniature history of the war :
- Creator:
- Ensor, R. C. K.
- Type:
- text and brožury
- Subject:
- Dějiny Evropy, válka druhá světová (1939-1945), světové dějiny 1939-1945, vojenské operace, války, bitvy, and odboj, odpor, antifašismus, antikomunismus
- Language:
- English
- Rights:
- unknown
1543. A miniature history of the war :
- Creator:
- Ensor, R. C. K.
- Type:
- text and monografie
- Subject:
- Vojenství. Obrana země. Ozbrojené síly, válka druhá světová (1939-1945), vojenské operace, války, bitvy, and světové dějiny 1939-1945
- Language:
- English
- Description:
- First part of book based on the author's Oxford pamphlet, "The uphill war", published in 1944
- Rights:
- unknown
1544. A mixture of diethylhexyl, diisononyl and dibutyl phthalate decreased anogenital distance, postnatal testosterone levels, and changed social behaviour in Wistar rats
- Creator:
- Morová, Martina, Senko, Tomáš, Olexová, Lucia, Dzirbíková, Zuzana, and Kršková, Lucia
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- phthalate mixture, testosterone, anogenital distance, social behavior, and laboratory rat
- Language:
- English
- Description:
- Phthalates are chemicals interfering with the function of testosterone and are suspected to play a role in the emergence of neurodevelopmental diseases. This could be due to interference with brain development for which optimal testosterone levels are essential. We investigated the effect of prenatal and early postnatal exposure to a phthalate mixture on the anogenital distance (AGD), plasma testosterone levels and social behavior in rats. Pregnant rats were exposed to a mixture of diethylhexyl, diisononyl and dibutyl phthalate, each at a dose of 4.5 mg/kg/day, from gestational day 15 to postnatal day 4. A social interaction test was performed to assess sociability in the three ontogenetic stages (weaning, puberty, adulthood). AGD was measured in adulthood to assess changes in prenatal testosterone levels. Plasma testosterone levels were measured in adults by a radioimmunoassay. The total frequency and time of socio-cohesive interactions were decreased in phthalate exposed females in weaning, puberty and adulthood. Phthalate exposed males showed a decrease in the frequency of social interactions in weaning only. Shorter anogenital distance was observed in adult males exposed to phthalates. Decreased testosterone levels were observed in the exposed group in both sexes. Our results suggest that early developmental phthalate exposure may play an important role in the hormonal and behavioral changes associated with several neurodevelopmental diseases.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1545. A mixture of support vector machines for time series forecasting
- Creator:
- Cao, Lijuan and Jingqing , Zhang
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Non-stationarity: support vector machines mixture and self-organizing feature map
- Language:
- English
- Description:
- A mixture of support vector machines (SVMs) is proposed for time series forecasting. The SVMs mixture is composed of a two-stage architecture. In the first stage, self-organizing feature map (SOM) is used as a clustering algorithm to partition the whole input space into several disjointed regions. A tree-structured architecture is adopted in the partition to avoid the problem of predetermining the number of partitioned regions. Then, in the second stage, multiple SVMs, also called SVM mixture, that best fit partitioned regions are constructed by finding the most appropriate kernel function and the optimal free parameters of SVMs. The experiment shows that the SVMs mixture achieves significant improvement in the generalization performance in comparison with the single SVMs model. In addition, the SVMs mixture also converges faster and use fewer support vectors.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1546. A model of artificial neuronal networks designed according the natural neuronal brain structures
- Creator:
- Kolda, T., Faber, J., Svoboda, P., and Dvořák, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- time dependent artificial network, genetic algorithm, stochastic training, brain structures, parallel computation, and formator - complex
- Language:
- English
- Description:
- The functional structure of our new network is not preset; instead, it comes into existence in a random, stochastic manner. The anatomical structure of our model consists of two input “neurons”, hundreds up to five thousands of hidden-layer “neurons” and one output “neuron”. The proper process is based on iteration, i.e., mathematical operation governed by a set of rules, in which repetition helps to approximate the desired result. Each iteration begins with data being introduced into the input layer to be processed in accordance with a particular algorithm in the hidden layer; it then continues with the computation of certain as yet very crude configurations of images regulated by a genetic code, and ends up with the selection of 10% of the most accomplished “offspring”. The next iteration begins with the application of these new, most successful variants of the results, i.é., descendants in the continued process of image perfection. The ever new variants (descendants) of the genetic algorithm are always generated randomly. The determinist rule then only requires the choice of 10% of all the variants available (in our case 20 optimal variants out of 200). The stochastic model is marked by a number of characteristics, e.g., the initial conditions are determined by different data dispersion variance, the evolution of the network organisation is controlled by genetic rules of a purely stochastic nature; Gaussian distribution noise proved to be the best “organiser”. Another analogy between artificial networks and neuronal structures lies in the use of time in network algorithms. For that reason, we gave our networks organisation a kind of temporal development, i.e., rather than being instantaneous; the connection between the artificial elements and neurons consumes certain units of time per one synapse or, better to say, per one contact between the preceding and subsequent neurons. The latency of neurons, natural and artificial alike, is very importaiit as it enables feedback action. Our network becomes organised under the effect of considerable noise. Then, however, the amount of noise must subside. However, if the network evolution gets stuek in the local minimum, the amount of noise has to be inereased again. While this will make the network organisation waver, it will also inerease the likelihood that the erisis in the local minimum will abate and improve substantially the state of the network in its self-organisation. Our system allows for constant state-of-the-network reading by ineaiis of establishing the network energy level, i.e., basically ascertaining progression of the network’s rate of success in self-organisation. This is the principal parameter for the detection of any jam in the local minimum. It is a piece of input information for the formator algorithm which regulates the level of noise in the system.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1547. A model of focusing in political choice
- Creator:
- Nunnari, Salvatore and Zápal, Jan
- Publisher:
- CERGE-EI
- Format:
- electronic, svazek, and 46 stran : ilustrace.
- Type:
- model:monograph and TEXT
- Subject:
- Volby, volební kampaně, referenda, volební chování, polarizace (sociologie), behaviorismus (politologie), electoral behavior, polarization (sociology), behaviorism (political science), 324:316.62, 316.4.063.24, 321:316.275, (048.8), 15, and 324
- Language:
- English and Czech
- Description:
- Salvatore Nunnari, Jan Zápal., Obsahuje bibliografii a bibliografické odkazy, Anglické a české resumé, and born digital
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1548. A model of rock mass fracturing ahead of the longwall face as a consequence of intensity of exploitation
- Creator:
- Drzewiecki, Jan and Makówka, Janusz
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, 7, and 551
- Language:
- English
- Description:
- In Czech and Polish underground hard coal mines of the Upper Silesian Coal Basin high-energy seismic phenomena are periodically recorded, the sources of which are located ahead of the longwall. Generally, these types of tremors are rooted in very strong, thick layers of sandstone, which are subject to the deformation border. The consequences are discontinuities and cracks with a range depending on the mechanical properties of destroyed rocks: the mechanical parameters of layers. Forecasting methods, developed in the Central Mining Institute, for stress concentration, seismic energy, fault zone and range, together with methods of rock fracturing using liquid or explosives, ,allow precise identification of suitable locations for controlled fracturing of rock mass with a pre-established direction. The size and range of discontinuities have an impact on mining parameters, dependent on basic exploitation intensity and expressed by the average daily progress of the longwall face. The rockmass is locally weakened because of exploitation or technical measures of discontinuities in the roof-rock on the longwall face. To prevent rockburst, measures are needed to reduce the amount of energy accumulating in the rockmass in the area of the longwall face. Knowledge of where stress is concentrated is extremely important for the development and implementation of effective preventative methods. For many years several research centres have been working on defining the range of these areas. In this paper, basic information is presented on methods developed by Central Mining Institute and used in Polish hard coal mines for forecasting energy concentration and assessing how it can be reduced., Jan Drzewiecki and Janusz Makówka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1549. A model of stochastic activity of neurone in some types of gaussian input processes
- Creator:
- Novák, V. and Schmidt, J.
- Type:
- article, model:article, and TEXT
- Subject:
- model of neuronal stochastic activity, e-curves, interspike interval density distribution, and stochastic transformations
- Language:
- English
- Description:
- A new approach to computer modelling of neuronal stochastic activity is described. The output dynamic activity which depends on the types and the number of input synapses, weights of the synaptic efficacy, the absolute refractory phase duration and threshold level is evaluated on this model in some types of Gaussian input processes. The behaviour of this model for one excitatory and one inhibitory synapse is described in dependence on the changes of excitation weight. The neuronal behaviour presented depends on the number of interspike intervals and the excitation weight and interspike interval density distribution. A novel concept of the e-curve is being introduced, which shows the dependence of the number of output interspike intervals on the weight of excitation on a stable inhibition level, the absolute refractory phase value and the threshold level. The properties of e-curves are discussed. Furthermore, examples of transformations of input stochastic processes are mentioned from the aspect of density distribution changes of interspike intervals.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1550. A modification of the Hartung-Knapp confidence interval on the variance component in two-variance-component models
- Creator:
- Arendacká, Barbora
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- variance components, approximate confidence intervals, and mixed linear models
- Language:
- English
- Description:
- We consider a construction of approximate confidence intervals on the variance component σ21 in mixed linear models with two variance components with non-zero degrees of freedom for error. An approximate interval that seems to perform well in such a case, except that it is rather conservative for large σ21/σ2, was considered by Hartung and Knapp in \cite{hk}. The expression for its asymptotic coverage when σ21/σ2→∞ suggests a modification of this interval that preserves some nice properties of the original and that is, in addition, exact when σ21/σ2→∞. It turns out that this modification is an interval suggested by El-Bassiouni in \cite{eb}. We comment on its properties that were not emphasized in the original paper \cite{eb}, but which support use of the procedure. Also a small simulation study is provided.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public