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A rebuttal to Mr. Sven Hunhammar's technical note is offered. It is stressed that the Nitta and Yoda paper intended to present a holistic scenario of the projected energy shortage without expressing any preference for any particular energy generating technology or forecasting method. Also, the authors explain that their representation of the growth rate in solar cell production accurately represents historical reality.  相似文献   
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In this paper, we propose an interactive constrained independent topic analysis in text data mining. Independent topic analysis (ITA) is a method for extracting independent topics from document data using independent component analysis. In this independent topic analysis, the most independent topics between each topic are extracted. By extracting the independent topic, managing documents with a large number of text data is easy with document access support systems and document management systems. However, the topics extracted by ITA are often different from the topics a user requests. For the system to be of service to users, an interactive system that reflects the user’s requests is necessary. Thus, we propose an interactive ITA that works for the user. For example, if there are three topics, i.e., topic A, topic B, and topic C, and a user choose the content from topics A and B, a user can merge those topics into one topic D. In addition, if a user wants to analyze topic A in more detail, a user could separate topic A into topics E and topic F. To that end, we define Merge Link constraints and Separate Link constraints as user requests. The Merge Link constraint is a constraint that merges two topics into one topic. The Separate Link constraint is a constraint that separates two topics from one topic. In this paper, we propose a method for extracting a highly independent topic that meets these constraints. We conducted evaluation experiments on our proposed methods, and obtained results to show the effectiveness of our approach.  相似文献   
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The great increase in world population in the coming century will result in a human crisis of worldwide proportions. A new concept for describing and proposing solutions to this crisis, called the Trilemma, is described by the authors. To feed large and growing populations, humankind is now being forced to make the difficult choice between producing sufficient food for the world population and preserving the environment, or generating economic growth, requiring the consumption of energy and natural resources. These difficult choices present the Trilemma, a new concept that is composed of three dimensions: economic growth, resources such as energy and food, and the environment. None of these three dimensions can be optimized individually as they are mutually interdependent.This paper describes a possible world energy condition in the 21st century. Three scenarios of this energy consumption are presented and compared with the possible energy supply at that time. This supply is estimated from the extrapolation of the renewable energy development of the past and the possible fossil fuel supply. The comparison of the energy supply and the energy consumption indicates that the annual rate of economic growth in the developed region would be only 1% if the gross national product (GNP) per capita of the developing region increases gradually from 1/26 of the GNP of the developed regions in 1990, to 1/10 in 2020, and finally to 1/3 in 2100.Another possibility is that if the GNP per capita of the developing region remains 1/26 of the GNP of the developed regions between 1990 and 2100, the economic growth rate in the developed region could be as large as 3%. In the latter case, an energy shortage would develop in the middle of the 21st century, even if the fast breeder reactor were fully operational by the year 2030. Energy technological developments in Japan are also described as a part of the possible countermeasures against the Trilemma.  相似文献   
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Building off the resource‐based view and the knowledge‐based view, our study aims to examine determinants of firms’ R&D outsourcing, using annually‐conducted firm‐level survey data of Japanese R&D companies from 1984–2012. This survey allows us to measure strategic R&D outsourcing, isolated from those more for cost‐reducing, such as prototyping, testing and inspecting. The results corroborate the argument of complementarity in scale between internal R&D and R&D outsourcing. We also find that firms employing more doctorate holders and diversifying in knowledge spaces tend to make more use of R&D outsourcing. This study sheds light on firms’ absorptive capacity, associated both with higher‐order R&D human capital and diversified knowledge spaces, as determinants of R&D outsourcing.  相似文献   
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The effects of direct payments on rice income variability in Japan are analysed based on a balanced panel dataset of Japanese rice farms for 2012–2016. Firstly, the contribution of income components to rice income variability and the effects of a direct payment reduction are discussed by applying variance decomposition. Secondly, robust regression techniques are used to measure the correlation between direct payments and rice income variability. The originality of this paper is that it disaggregates the effects of payments using a regression analysis of the effects of direct payments on income variability for Japan. This contrasts with the existing literature on this topic, which has largely focused on European Union countries. This paper discusses to what degree the reduction in direct payments increases income variability. The results reveal that direct payments decrease Japanese rice income variability. Indeed, after controlling for various farm characteristics, we find a negative relationship between the amount of direct payments linked to rice production and rice income variability. Finally, the results suggest that reducing direct payments when the rice price is falling would increase rice income variability.  相似文献   
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