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1.
Infrastructural and societal changes intertwine in multiple ways. This makes the societal implications of infrastructural projects difficult to assess and anticipate. Yet in present day network societies this task is particularly urgent. This paper first identifies two positions that tend to monopolize and deadlock debates. Next it examines two decades of research in the Large Technical System (LTS) research field for alternative approaches to this issue, before finally suggesting distinguishing between the four increasingly indirect moments of (co-) construction of infrastructures and societies. These may be related causally, but also add their own moments of contingency, agency, and choice.  相似文献   
2.
Recent approaches to sustainable development leave much room for policies at a local level. In fact, it is becoming evident that targets such as increasing resource productivity, preserving natural cycles, or extending the present level of welfare, are best pursued within the confines of a local area. In particular, environmental changes are best brought about by considering local systems of firms as cornerstones of cooperative strategies and using data on materials and energy use in physical terms. In this paper, an enterprise input–output model is developed for an industrial district, i.e. a local group of firms specialized in the production of a single final output. The model allows for a detailed quantitative analysis of materials and energy flows and the consequent generation of waste and pollution. As a planning tool, the model may be used to evaluate alternative scenarios, such as the possibility of re- using waste taking account of sustainability requirements. An empirical case study applies the model to an industrial district in Southern Italy producing leather sofas.  相似文献   
3.
Despite the fact that international technology transfer has been widely studied its management still encounters many difficulties. To fully understand the issues that are relevant to the process of transferring production technology, it is necessary to determine the important factors that influence this process. Learning curves are often used as a means of determining the time required to become familiar with a transferred technology. The cases discussed in this paper have all employed learning curves, which were established at the outset of the transfer process and which turned out to be incorrect. As a consequence the envisaged efficiencies were not obtained. This phenomenon is partly due to the fact that when technology is transferred to a relatively inexperienced 'destination company', the curve is established based on the circumstances of the 'source company'. The case study findings lead to the conclusion that to establish a realistic curve a more comprehensive method is required than simply basing anticipated performance on that achieved at the source company.  相似文献   
4.
Trade unions have a rational incentive to oppose the adoption of labour-saving technology when labour demand is inelastic and unions care much for employment relative to wages. Trade liberalisation typically increases trade union technology opposition. These conclusions are reached in a model of unionised international duopoly with two-way trade. We also find that the incentive for technology opposition is stronger in the more technologically advanced country and in the country with the larger home market, complementing earlier explanations for technological catch-up and leapfrogging.  相似文献   
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A system of regression equations for analyzing panel data with random heterogeneity in intercepts and coefficients, and unbalanced panel data is considered. A maximum likelihood (ML) procedure for joint estimation of all parameters is described. Since its implementation for numerical computation is complicated, simplified procedures are presented. The simplifications essentially concern the estimation of the covariance matrices of the random coefficients. The application and ‘anatomy’ of the proposed algorithm for modified ML estimation are illustrated by using panel data for output, inputs and costs for 111 manufacturing firms observed up to 22 years.  相似文献   
7.
A generalization is presented of the existence results for an optimal consumption problem of Aumann and Perles [4] and Cox and Huang [10]. In addition, we present a very general optimality principle. Received: July 14, 1999; revised version: September 9, 1999  相似文献   
8.
Let be a sequence of differential information economies, converging to a limit differential information economy (written as ). Denote by the set of all ε-private core allocations, ε ≥ 0 (for ε=0 we get the private core of Yannelis (1991), denoted by ). Under appropriate conditions, we prove the following stability results
(1) (upper semicontinuity): if , , and if f k f L 1-weakly, then .
(2) (lower semicontinuity): if , , ε > 0, then there exist , with f k f L 1-weakly.
JEL Classification Numbers D82, D50, D83, C62, C71, D46, D61Most of this work was done in Spring 2001, when Balder held a visiting professorship at the University of Illinois. Presentations based on this paper were given by Balder at the Midwestern Theory Conference in Madison, Wisconsin (May, 2001) and at the SAET Conference in Ischia, Italy (June, 2001).  相似文献   
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Erik Koenen 《Publizistik》2018,63(4):535-556
In the discussion about the future of communication and media science in digital times, this article focuses on the position and perspective of communication and media history. The challenges, problems and potentials associated with digitization are illustrated using the example of historical press research. Within the media ensemble of classical mass communication, the periodic press in particular benefits from the retrospective digitization of historical media and their digital edition in databases and portals. For historical press research, digitized newspapers and digital newspaper portals represent an originally new, because increasingly digital research situation: Digital newspaper portals as a novel, originally digital world for newspapers not only facilitate the path to newspapers and their contents, they also open them up as digital resources machine-readable and thus open up completely new paths for research—not least supported by digital methods.The main objective of this article is to discuss the epistemological-methodological problems and the practical operationalization of digitally framed or supported research processes in historical press research and to present concrete perspectives of knowledge and research strategies for practice. With this aim in mind, the paper discusses three points:(1.) Methodological and practical consequences of historical press research in digital research environments. With the digitization of newspapers and their digital reproduction in newspaper portals, their source character shifts essentially in three dimensions: They are edited and indexed digitally and their complete content is made accessible through optical character recognition. This makes previously unimportant technical aspects such as data formats, portal interfaces, search algorithms and programming interfaces very relevant for the methodology of historical press research. A primary methodological effect of the digital reorganization of newspapers in data and portals is the reversal of the usual reading practice: from “top down” to “bottom up”. With the help of “keyword searching”, newspapers can now be searched comprehensively and transversely to the order of the newspaper original. Nevertheless, there is a warning against an all too naïve and uncritical usage of digitized newspapers and newspaper portals. In practice, some problems and risks are crucial for the conception of historical newspaper research in digital research environments: Besides a hardly standardized and in large parts “wild”, because often uncoordinated and selective digitization of newspapers, the newspaper portals are different in their conception as well as characterized by different content, technical, legal and entrepreneurial conditions.(2.) Historical newspapers as digital sources in practice. The methodological and technical framework are fundamental and far-reaching for the further practical use of newspapers as digital sources in research. In each research step, it must be considered that digitized newspapers are genuinely new and, depending on the quality and depth of digitization, very complex sources with information gains and losses compared to the originals. Newspapers are not simply digitized, they are digitally constructed and differ in this construction from each other. In this respect, historical press researchers are increasingly becoming “users”. However simple and uncomplicated newspaper portals may be in practice, one must incorporate the implicit functions (hidden in algorithms, data and code) and the limits of these knowledge engines and their “correct” use into the research process. Combining and mediating classical hermeneutic methods with search technologies is an essential moment in the practical handling of digitized newspapers.(3.) Historical press research and digital methods. In the light of the new research situation which is emerging with digitized newspapers and newspaper portals, it is obvious that historical press research should increasingly open up to the possibilities of digital methods. In the digital method discussion of historical press research, one concept in particular forms a central point of reference: Franco Moretti’s concept of “Distant Reading”. Basically, “Distant Reading”—and this is what makes this perspective so interesting for historical press research in dealing with the considerable metadata and full text volumes of digitized newspapers—is about the quantitative-automatic indexing of large text corpora using methods and techniques of “Text Mining”. Digital text methods are thus seriously changing the way we look at texts and the research practice with texts such as newspapers: In parts, they automate and accelerate reading processes, produce “new” text extracts by the computer, generate new interpretation contexts between individual text, corpus and condensate, and thus set new orientation points for “close reading”. Computers and digital text methods thus do not relieve researchers of interpretation. Rather, they constantly challenge them to interpret in a continuous interplay in order to give meaning to the text patterns discovered by machines.In spite of all these advantages, digital methods have so far only been used sporadically in historical press research. For this reason, finally a digital workflow for research processes in historical press research will be presented, which illustrates and summarizes essential challenges, problems, solutions and potentials of digitally framed or supported research in press history.  相似文献   
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