891 resultados para basis of the solution space of a homogeneous sparse linear system
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The problems of formalization of the process of matching different management subjects’ functioning characteristics obtained on the financial flows analysis basis is considered. Formal generalizations for gaining economical security system knowledge bases elements are presented. One of feedback directions establishment between knowledge base of the system of economical security and financial flows database analysis is substantiated.
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The system of development unstable processes prediction is given. It is based on a decision-tree method. The processing technique of the expert information is offered. It is indispensable for constructing and processing by a decision-tree method. In particular data is set in the fuzzy form. The original search algorithms of optimal paths of development of the forecast process are described. This one is oriented to processing of trees of large dimension with vector estimations of arcs.
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The evaluation from experimental data, of physical quantities, which enter into the electromagnetic Maxwell equations, is described as inverse optical problem. The functional relations between the dependent and independent variables are of transcendental character and numeric procedures for evaluation of the unknowns are largely used. Herein, we discuss a direct approach to the solution, illustrated by a specific example of determination of thin films optical constants from spectrophotometric data. New algorithm is proposed for the parameters evaluation, which does not need an initial guess of the unknowns and does not use iterative procedures. Thus we overcome the intrinsic deficiency of minimization techniques, such as gradient search methods, Simplex methods, etc. The price of it is a need of more computing power, but our algorithm is easily implemented in structures such as grid clusters. We show the advantages of this approach and its potential for generalization to other inverse optical problems.
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Methodological, theoretical and technological bases of the new branch standard of Ukraine higher education which regulates preparation process of masters - professionals in the information area and information analysts are considered. The new systemological knowledge-oriented technologies developed in KNURE which considerably surpass foreign analogues are put as the basis of training.
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2000 Mathematics Subject Classification: 90C26, 90C20, 49J52, 47H05, 47J20.
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The article attempts to answer the question whether or not the latest bankruptcy prediction techniques are more reliable than traditional mathematical–statistical ones in Hungary. Simulation experiments carried out on the database of the first Hungarian bankruptcy prediction model clearly prove that bankruptcy models built using artificial neural networks have higher classification accuracy than models created in the 1990s based on discriminant analysis and logistic regression analysis. The article presents the main results, analyses the reasons for the differences and presents constructive proposals concerning the further development of Hungarian bankruptcy prediction.
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The Leontief input-output model is widely used to determine the ecological footprint of consumption in a region or a country. It is able to capture spillover environmental effects along the supply change, thus its popularity is increasing in ecology related economic research. These studies are static and the dynamic investigations are neglected. The dynamic Leontief model makes it possible to involve the capital and inventory investment in the footprint calculation that projects future growth of GDP and environmental impacts. We show a new calculation method to determine the effect of capital accumulation on ecological footprint. Keywords: Dynamic Leontief model, Dynamic ecological footprint, Environmental management, Allocation method
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This paper describes the results of an investigation into the finance-related innovative ability of Hungarian micro, small and medium sized enterprises (SMEs) by using two datasets (from 2006 and 2010). The author explored SMEs’ levels of openness to new financial solutions and identified features which influence their innovative solution-seeking behavior. Additionally, changes in innovation between 2006 and 2010 were analyzed according to the SME sector and whether there is a correlation between having an active solution seeking attitude and business performance was examined. The findings show that shared/multiple ownership in businesses (having interests in different enterprises simultaneously) has a significant positive effect on flexibility and innovative ability. However, the size of the business, industrial sector, type of ownership and market of the SME also have some effect. Furthermore, the hypothesis that an active solution-seeking attitude increases after-tax performance per employee was confirmed.
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In our study we rely on a data mining procedure known as support vector machine (SVM) on the database of the first Hungarian bankruptcy model. The models constructed are then contrasted with the results of earlier bankruptcy models with the use of classification accuracy and the area under the ROC curve. In using the SVM technique, in addition to conventional kernel functions, we also examine the possibilities of applying the ANOVA kernel function and take a detailed look at data preparation tasks recommended in using the SVM method (handling of outliers). The results of the models assembled suggest that a significant improvement of classification accuracy can be achieved on the database of the first Hungarian bankruptcy model when using the SVM method as opposed to neural networks.
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A szervezet dolgozói között kiemelt fontosságúak a vezetők, hiszen döntéseikkel, működésükkel a szervezet életét közvetlenül, és sokszor hosszú távra befolyásolják. Annak a vállalatnak, mely megtartani, növelni szeretné piaci pozícióját, különös hangsúlyt kell fektetnie vezetőinek kiválasztására, a későbbiekben pedig fejlesztésére. A szerző cikkében azt mutatja be, hogy a közgazdászképzettséggel rendelkező vezetők iránti munkaerő-piaci kereslet (a HVG-hirdetések elemzése alapján) milyen minőségi jellemzőket mutatott 2000–2009 között. A szerző részletesen ismerteti az eredményeket, melyek értelmezéséhez a Spencer és munkatársai által kidolgozott kompetenciamodell saját továbbfejlesztett változatát használja fel. Kitekintés céljával a magyar eredmények mellett bemutatja, hogy egy más gazdasági struktúrával, kultúrával rendelkező országban hogyan alakultak a vezetőkkel szemben támasztott kompetencia-elvárások. Az eredmények – melyeket más hazai felmérések is alátámasztanak – azt tükrözik, hogy a magyar vezetőkkel szemben támasztott munkaerő-piaci kompetencia-elvárások eltérnek a szakmai várakozásoktól és élesen eltérő képet mutatnak a The Economist hirdetéselemzésének eredményétől. _________ The thesis that the most important factor which determines the competitiveness of future companies is the quality of human resources has received increasingly more emphasis in the literature on management. The managers of organizations have a key role since they can directly influence the life of the organization by their decisions and work, often for a long term. Therefore, a company which intends to maintain or improve its market position should place special emphasis on the selection, and later on the development of its managers. In the present paper the author presents the characteristic features of job market demand for managers with qualifications in economics between 2000 and 2009 (on the basis of the analysis of job advertisements published in the economic weekly paper Heti Világgazdaság). The author gives a detailed analysis of the results using the competence model developed by Spencer et al. and further developed by the author. In addition to the Hungarian results, the paper also provides an overview of how managers are selected in a country with a different economic structure and culture. The results – also supported by other surveys conducted in Hungary – demonstrate that the competence expectations of the job market for Hungarian managers fail to meet professional expectations; the picture is sharply different from what the analysis of job advertisements published in The Economist show, and the competence expectation changed very little, though quite strikingly, over the period under discussion.
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Smaller class sizes have a positive impact on student achievement but Florida struggles with the problem of how to achieve smaller classes. Through a review of the literature, this paper discusses some of the programs currently used across the US, with the focus on Florida. Conclusions and implications are presented.
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Since 1999, Venezuela has experienced a dramatic transformation of its political system with the coming to power of Hugo Chávez and his movement, known in Venezuela as Chavismo. Chávez has dismantled the previous political system and established neo-populist structures that rely on his personal appeal and the close collaboration of the armed forces. Chávez has relied heavily on significant support from the poor and those who felt economically and politically excluded by the “Punto Fijo system.” President Chávez has built an impressive record of electoral victories; winning every electoral contest except one since coming to power in 1999. He continues to receive relatively high levels of support among sectors of Venezuelan society. However, there is evidence of growing discontent with high crime rates, high levels of inflation, and significant corruption in the public administration. Using data from the AmericasBarometer surveys conducted in 2007, 2008 and 2010, this paper seeks to examine the basis of Chávez’s popular support. In general, the AmericasBarometer findings suggest that Venezuelans support for President Chávez is closely linked to the access to social programs and that as long as the government is able to fund these social programs or missions, particularly MERCAL and Barrio Adentro, it will possess an important tool to garner and sustain support for President Chávez. Our analysis, however, also indicates that evaluations of the national economic situation, more than crime or insecurity, are a key factor that could undermine support for the regime.
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Involuntary episodic memories are memories that come into consciousness without preceding retrieval effort. These memories are commonplace and are relevant to multiple mental disorders. However, they are vastly understudied. We use a novel paradigm to elicit involuntary memories in the laboratory so that we can study their neural basis. In session one, an encoding session, sounds are presented with picture pairs or alone. In session two, in the scanner, sounds-picture pairs and unpaired sounds are reencoded. Immediately following, participants are split into two groups: a voluntary and an involuntary group. Both groups perform a sound localization task in which they hear the sounds and indicate the side from which they are coming. The voluntary group additionally tries to remember the pictures that were paired with the sounds. Looking at neural activity, we find a main effect of condition (paired vs. unpaired sounds) showing similar activity in both groups for voluntary and involuntary memories in regions typically associated with retrieval. There is also a main effect of group (voluntary vs. involuntary) in the dorsolateral prefrontal cortex, a region typically associated with cognitive control. Turning to connectivity similarities and differences between groups again, there is a main effect of condition showing paired > unpaired sounds are associated with a recollection network. In addition, three group differences were found: (1) increased connectivity between the pulvinar nucleus of the thalamus and the recollection network for the voluntary group, (2) a higher association between the voluntary group and a network that includes regions typically found in frontoparietal and cingulo-opercular networks, and (3) shorter path length for about half of the nodes in these networks for the voluntary group. Finally, we use the same paradigm to compare involuntary memories in people with posttraumatic stress disorder (PTSD) to trauma-controls. This study also included the addition of emotional pictures. There were two main findings. (1) A similar pattern of activity was found for paired > unpaired sounds for both groups but this activity was delayed in the PTSD group. (2) A similar pattern of activity was found for high > low emotion stimuli but it occurred early in the PTSD group compared to the control group. Our results suggest that involuntary and voluntary memories share the same neural representation but that voluntary memories are associated with additional cognitive control processes. They also suggest that disorders associated with cognitive deficits, like PTSD, can affect the processing of involuntary memories.