In this paper,we study the computative structure of computable function-a structure of computative tree,and,by analysis on it,got the most general algorithm and model for computation on computable functions.
Introduction:This paper presents basic information on the research,classification,and application of the functions of tree species and their communities(mainly forest)in Slovakia.The main aim is a scientific assessmen...Introduction:This paper presents basic information on the research,classification,and application of the functions of tree species and their communities(mainly forest)in Slovakia.The main aim is a scientific assessment of acquired knowledge regarding the functional effects of forests under real ecological,forest management and socio-economic conditions from various regions in Slovakia;the most up-to-date findings concerning the ecology and economics of natural resources will be applied here.The second part of the paper presents methodological possibilities for valuation of outdoor recreation in forests.Different methods and methodological approaches suitable to a valuation of recreation based on various principles and criteria(preference and non-preference methods,cost-based methods,revenue-based methods,and direct and indirect methods)are analyzed.A practical application of one indirect preference method(travel cost method)is made to evaluate outdoor recreation in forests in Slovakia.Results and conclusions:A new classification system and a methodology of integrative utilization of forest functions for the forest ecosystem services are constructed.Outdoor recreation in forests,besides recreational forests and areas,assumes the character of a public good:its use by individuals has some influence on utilization by other individuals,and single users cannot be excluded from its utilization.Therefore,some stimulation for its production is missing.In principle,there are no markets for these kinds of public goods and services.The total value of outdoor recreation in forests in Slovakia amounted to€163.4 million;if opportunity time costs were included,this amounted to as much as€825.7 million.展开更多
We fix a counting function of multiplicities of algebraic points in a projective hypersurface over a number field, and take the sum over all algebraic points of bounded height and fixed degree. An upper bound for the ...We fix a counting function of multiplicities of algebraic points in a projective hypersurface over a number field, and take the sum over all algebraic points of bounded height and fixed degree. An upper bound for the sum with respect to this counting function will be given in terms of the degree of the hypersurface, the dimension of the singular locus, the upper bounds of height, and the degree of the field of definition.展开更多
基金supported by National Natural Science Foundation of China.
文摘In this paper,we study the computative structure of computable function-a structure of computative tree,and,by analysis on it,got the most general algorithm and model for computation on computable functions.
基金This publication is the result of the project implementation:Extension of the centre of Excellence‘Adaptive Forest Ecosystems’,ITMS:26220120049supported by the Research&Development Operational Programme funded by the ERDF.
文摘Introduction:This paper presents basic information on the research,classification,and application of the functions of tree species and their communities(mainly forest)in Slovakia.The main aim is a scientific assessment of acquired knowledge regarding the functional effects of forests under real ecological,forest management and socio-economic conditions from various regions in Slovakia;the most up-to-date findings concerning the ecology and economics of natural resources will be applied here.The second part of the paper presents methodological possibilities for valuation of outdoor recreation in forests.Different methods and methodological approaches suitable to a valuation of recreation based on various principles and criteria(preference and non-preference methods,cost-based methods,revenue-based methods,and direct and indirect methods)are analyzed.A practical application of one indirect preference method(travel cost method)is made to evaluate outdoor recreation in forests in Slovakia.Results and conclusions:A new classification system and a methodology of integrative utilization of forest functions for the forest ecosystem services are constructed.Outdoor recreation in forests,besides recreational forests and areas,assumes the character of a public good:its use by individuals has some influence on utilization by other individuals,and single users cannot be excluded from its utilization.Therefore,some stimulation for its production is missing.In principle,there are no markets for these kinds of public goods and services.The total value of outdoor recreation in forests in Slovakia amounted to€163.4 million;if opportunity time costs were included,this amounted to as much as€825.7 million.
文摘We fix a counting function of multiplicities of algebraic points in a projective hypersurface over a number field, and take the sum over all algebraic points of bounded height and fixed degree. An upper bound for the sum with respect to this counting function will be given in terms of the degree of the hypersurface, the dimension of the singular locus, the upper bounds of height, and the degree of the field of definition.
