873 publications from this institution
Versuche zur Anwendung wurzelanatomischer Untersuchungen als Frühselektionsmethode in der Apfelunterlagen-Züchtung was published in Band 18, Heft 1 1970 on page 53.
This paper presents a methodology for neural spatial interaction modelling. Particular emphasis is laid on design, estimation and performance issues in both cases, unconstrained and singly constrained spatial interaction. Families of classical neural network models, but also less classical ones such as product unit neural network models are considered. Some novel classes of product unit and summation unit models are presented for the case of origin or destination constrained spatial interaction flows. The models are based on a modular connectionist architecture that may be viewed as a linked collection of functionally independent neural modules with identical feedforward topologies, operating under supervised learning algorithms. Parameter estimation is viewed as Maximum Likelihood (ML) learning. The nonconvex nature of the loss function makes the Alopex procedure, a global search procedure, an attractive and appropriate optimising scheme for ML learning. A benchmark comparison against the classical gravity models illustrates the superiority of both, the unconstrained and the origin constrained, neural network model versions in terms of generalization performance measured by Kullback and Leibler`s information criterion. Hereby, the authors make use of the bootstrapping pairs approach to overcome the largely neglected problem of sensitivity to the specific splitting of the data into training, internal validation and testing data sets, and to get a better statistical picture of prediction variability of the models. Keywords: Neural spatial interaction models, origin constrained or destination constrained spatial interaction, product unit network, Alopex procedure, boostrapping, benchmark performance tests.
This paper attempts to elaborate the theory of random utility maximizing discrete choice behaviour in the context of regional labour supply mobility. From
In 5 patients with pheochromocytoma and 1 patient with a pheochromoblastoma, 131I-meta-iodobenzylguanidine was used to localize hyperfunktioning adrenergic tissue. Except in one patient, a correct localization of the tumors was obtained. Three patients had an intraadrenal pheochromocytoma of the left adrenal gland, 1 patient a retropancreatic pheochromoblastoma and 1 patient multilocular pheochromocytoma with tumors in both renal hili, in the supraclavicular region and in the bones. In one patient with a pheochromocytoma of the right adrenal, no clearcut visualization of the tumor could be observed. In this patient, in contrast to the other examinations, a specific activity of 2 mCi/mg benzylguanidine was used (0.2 mCi/mg benzylguanidine in the other patients). Thus, the amount of benzylguanidine given for each scan was 10fold higher in the patients with a correct localization. The present results document the claim that scintigraphy with 131I-benzylguanidine is a safe and reliable method of detecting both benign and malignant adrenal and extra-adrenal pheochromocytoma. To separate the pheochromocytoma from the adjacent tissue, additional computed tomography should be performed.
In Wohnhäusern betriebene Chemische Reinigungen können Wohnungen und darin gelagerte Lebensmittel mit Tetrachlorethen (Perchlorethylen) und ander
Interest of STI policies to influence the innovation behaviour of firms has been increased considerably. This gives rise to the notion of behavioural additionality, broadening traditional evaluation concepts of input and output additionality. Though there is empirical work measuring behavioural additionalities, we know little about what role distinct firm characteristics play for their occurrence. The objective is to estimate how distinct firm characteristics influence the realisation of behavioural additionalities. We use survey data on 155 firms, considering the behavioural additionalities stimulated by the Austrian R&D funding scheme in the field of intelligent transport systems in 2006. We focus on three different forms of behavioural additionality—project additionality, scale additionality and cooperation additionality—and employ binary regression models to address this question. Results indicate that R&D related firm characteristics significantly affect the realisation of behavioural additionality. R&D intensive firms are less likely to substantiate behavioural additionalities, while small, young and technologically specialised firms more likely realise behavioural additionalities. From a policy perspective, it may be concluded that direct R&D promotion of firms with a high R&D intensity may be misallocated. Attention of public support should be shifted to smaller, technologically specialised firms with lower R&D experience. The findings deliver important insights into interactions of public R&D support and R&D behaviour of firms operating in the Austrian transport sector, bearing significant implications for future policy designs.
The hypothesis in this paper is that the existence of retail markets may not necessarily be determined by spatial factors and increasing return in transportation (or increasing returns in retailing), but can be explained by the rational behaviour of firms operating in a stochastic environment. It is shown that demand uncertainty can serve as an independent source of retail trade. Consequently, the ability of firms to process information and predict demand (i.e. to decrease demand uncertainty) may affect the characteristics of retail markets. The results indicate that risk-averse firms always devote resources to demand forecasting; producers are better off trading with retailers than with final consumers; and the volume of output supplied through retail markets is greater than it would be if producers traded directly with consumers (thus benefiting social welfare). Furthermore, the contribution shows that technological progress in data-processing, which allows for cheaper and better predictions of market demand, increases the number of firms operating in retail markets.
Inflammatory joint diseases as well as arthropathy are common joint diseases. Many of them may be treated by synovectomy to stop disease progression and to improve joint function. Radiosynoviorthesis as one therapeutic procedure of rheumatoid arthritis, other inflammatory joint diseases, persistent synovial perfusion, and other joint diseases is widely used in many countries in Europe. Using Y-90 for the knee joint, Re-186 for middle sized joints and Er-169 for small joints an improvement of symptoms and function may be observed in about 60-80% of patients.
No abstract is provided for this article.
We attempt to clarify a number of points regarding use of spatial regression models for regional growth analysis. We show that as in the case of non-spatial growth regressions, the effect of initial regional income levels wears off over time. Unlike the non-spatial case, long-run regional income levels depend on: own region as well as neighbouring region characteristics, the spatial connectivity structure of the regions, and the strength of spatial dependence. Given this, the search for regional characteristics that exert important influences on income levels or growth rates should take place using spatial econometric methods that account for spatial dependence as well as own and neighbouring region characteristics, the type of spatial regression model specification, and weight matrix. The framework adopted here illustrates a unified approach for dealing with these issues.
ISHS VII International Symposium on Orchard and Plantation Systems THE FUTURE: RESISTANT APPLE CULTIVARS
Satellite images increasingly become a major data source for monitoring changes in the natural environment. A main task in the analysis of satellite images is concerned with the modelling of land use classes by reducing uncertainty during a classification process. In the approach presented in this paper uncertainty is perceived to be due to the vagueness of geographical categories caused by either the complexity of the category (like 'urban area') or by the use of the category in several application contexts. Two circumstances of use of an extended set theoretical concept (fuzzy sets) are discussed. First, two algorithms from the ISODATA class are used to determine the grades of membership to three a priori defined classes (woodland, suburban area, urban area) of a LANDSAT TM satellite image of Vienna, Austria. The results are visualized by a RGB image of the grades of membership to each category. Second, a measure of fuzziness is employed on the results. The measure relies on the concept of distance between a seUcategory and its complement. The so determined vagueness provide more information on the uncertainty of the different categories and may improve further information processing tasks. (authors' abstract)
No abstract is provided for this article.
No abstract is provided for this article.
22 ausgewahlte Arten der Familie Apiaceae werden durch analytische Zeichnungen illustriert. Die spezifischen Merkmale und ihr ontogenetischer Wandel werden dargestellt und um Angaben zu Wuchsform, Synokologie, Standortsbindung, interner und externer Verbreitung, Haufigkeit, floristischem Status und Gefahrdung in Osterreich erganzt. (42) Eryngium campestre , (43) E. giganteum , (44) E. alpinum , (45) E. planum , (46) Chaerophyllum villarsii , (47) Ch. hirsutum , (48) Bupleurum stellatum , (49) B. petraeum , (50) Trinia kitaibelii , (51) Conioselinum tataricum , (52) Peucedanum austriacum , (53) P. rablense , (54) Pimpinella alpina , (55) Seseli osseum und S. austriacum , (56) S. pallasii , (57) S. campestre , (58) Oenanthe banatica , (59) Heracleum austriacum , (60) Laserpitium halleri , (61) L. peucedanoides , (62) L. archangelica , (63) L. krapfii .
