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101.
This paper investigates the dynamic relationships between research and development (R&D) expenditure and productivity growth in Australian broadacre agriculture using aggregate time series data for the period 1953 to 2009. The results show a cointegrating relationship between R&D and productivity growth and a unidirectional causality from R&D to TFP (total factor productivity) growth in Australian broadacre agriculture. Using the dynamic properties of the model, data from beyond the sample period are analysed by employing the variance decomposition and the impulse response function. The findings reveal that R&D can be readily linked to the variation in productivity growth beyond the sample period. Furthermore, the forecasting results indicate that a significant out‐of‐sample relationship exists between public R&D and productivity in broadacre agriculture.  相似文献   
102.
Low agricultural productivity remains the primary source of poverty in the developing regions and yet little is known about the influence on agricultural productivity of domestic and international accumulated R&D knowledge and the channels through which this knowledge is transmitted internationally. Following a large scientific literature, this article argues that R&D and R&D knowledge spillover are ecozone‐specific and, therefore, are transmitted internationally through ecozones, where ecozones are the broadest biogeographic division of the earth's land surface. Using data for a panel of 88 countries, it is shown that international knowledge spillovers are ecozone‐specific and have been an important contributing factor behind the marked widening of the income gap between developed and developing countries since 1983.  相似文献   
103.
The complexity of modern farm management places great demands on the skill, knowledge and capability of farm managers and their families. Keeping abreast of emerging technologies and innovations that can affect each key farm enterprise, and knowing how best to marshal the resources required for profitable farm production, are key tasks of farm management. This study draws on a longitudinal data set of 240 broadacre farmers to compare and analyse their farm performance over a decade. Using structural equation modelling, we examine relationships between the farm family's involvement in training, their human capital, their use of various innovations and ultimately the linkages of these factors to farm financial and productivity performance. Several statistically significant inter‐relationships are found, and some factors are shown to have significant positive links to farm performance. We find that training undertaken by the farm family, the farm family's human capital and their use of innovations, particularly key cropping innovations, have significant beneficial impacts on farm performance. The farmer's skills in time and organisational management, their engagement in business planning and the unique environmental characteristics of the farm also significantly and positively influence farm performance.  相似文献   
104.
Using data for a long panel of 90 developed and developing countries, this article explores the effects of research and development (R&D) and fixed capital stock on agricultural land productivity over the period 1961–2012. Instruments are used for R&D to deal with feedback effects and measurement errors. The results show very high social returns to investment in R&D and to fixed capital stock, suggesting that increasing investment in these factors are promising ways of arresting the increasing food prices due to increasing demand for animal protein, population growth, desertification, salinization, soil erosion, climate change, and decreasing growth in land productivity.  相似文献   
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Transitioning towards a sustainable energy system requires the large-scale introduction of novel energy demand and supply technologies. Such novel technologies are often expensive at the point of their market introduction but eventually become cheaper due to technological learning. In order to quantify potentials for price and cost decline, the experience curve approach has been extensively applied to renewable and non-renewable energy supply technologies. However, its application to energy demand technologies is far less frequent. Here, we provide the first comprehensive review of experience curve analyses for energy demand technologies. We find a widespread trend towards declining prices and costs at an average learning rate of 18 ± 9%. This finding is consistent with the results for energy supply technologies and for manufacturing in general. Learning rates for individual energy demand technologies are symmetrically distributed around the arithmetic mean of the data sample. Absolute variation of learning rates within individual technology clusters of 7 ± 4%-points and between technology clusters of 7 ± 5%-points both contribute to the overall variability of learning rates. Our results show that technological learning is as important for energy demand technologies as it is for energy supply technologies. Applying the experience curve approach to forecast technology costs involves, however, unresolved uncertainties, as we demonstrate in a case study for the micro-cogeneration technology.  相似文献   
108.
Given that tourism is an “earthly business”, why is it that the Earth rarely explicitly appears in tourism studies and tourism theory? In an attempt to grapple with this paradox, this paper seeks to contribute to a conceptual re-cognition of the Earth in tourism theory by probing some theoretical obstacles and possibilities. The paper demonstrates how the Earth has been conceptually erased in tourism theory by a privileging of the mapping of tourism and tourists onto the reference plane of the social. As an alternative the paper seeks to provide a geo-philosophically informed conceptualisation of the Earth as a primary plane of reference of which tourism is a particular form of de/re-territorialisation.  相似文献   
109.
Dismantling dark networks remains a critical goal for the peace and security of our society. Terrorist networks are the most prominent instantiation of dark networks, and they are alive and well. Attempts to preemptively disrupt these networks and their activities have met with both success and failure. In this paper, we examine the impacts of four common strategies for dismantling terrorist networks. The four strategies are: leader-focused, grassroots, geographic, and random. Each of these strategies has associated pros and cons, and each has different impacts on the structure and capabilities of a terrorist network. Employing a computational experimentation methodology, we simulate a terrorist network and test the effects of each strategy on the resiliency of that network. In addition, we test scenarios in which the terrorist network has (or does not have) information about an impending attack. Our work takes a structural perspective to the challenge of addressing terrorist networks. Specifically, we show how various strategies impact the structure of the network in terms of its resiliency and capacity to carry out future attacks. This paper also provides a valuable overview of how to use agent-based modeling for the study of complex problems in the terrorism, conflict studies, and security study domains.  相似文献   
110.
Idea Competitions (ICs) are becoming a popular mechanism chosen by firms to perform Open Innovation. They are a way to engage with external sources of knowledge such as individual entrepreneurs and small firms who are asked to submit ideas and compete for a prize. However, little is known about the success of ICs as acquisition mechanisms. The researchers conducted interviews in five multinational companies to evaluate the effects of using ICs as an acquisition mechanism. Although still preliminary, the results of this study show that the success of ICs as an acquisition mechanism remains uncertain because their output (i.e. the number of ideas acquired) is often low compared to the input (i.e. the number of ideas submitted) and effort required to run them (e.g. to vet ideas). Across the cases observed, ICs appear to be more successful at identifying and acquiring early-stage ideas, particularly those outside the current business focus. The study shows that ICs deliver other functional benefits such as improved intelligence and public relations and that these need to be considered as part of the evaluation of the IC's success. The paper concludes by discussing the conditions in which ICs are implemented and the implications for Open Innovation theory.  相似文献   
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