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Biofortification of maize with provitamin A carotenoids is a new approach to the alleviation of vitamin A deficiencies in Africa. Unfortunately these varieties are yellow or orange, while consumers generally prefer white. Consumer willingness to pay for yellow and fortified maize was compared in experimental auctions in three regions in Kenya. The premium that consumers are willing pay for fortified maize (24%) was higher than the discount they require to buy yellow maize (11%), and in one zone consumers prefer yellow. Yellow color is, therefore, not an impossible obstacle for biofortified maize, although it would clearly be easier to introduce this maize first in regions where yellow maize is currently grown. 相似文献
164.
Methods and tools for integrated assessment of land use policies on sustainable development in developing countries 总被引:4,自引:0,他引:4
Pytrik Reidsma Hannes König Shuyi Feng Irina Bezlepkina Ingrid Nesheim Muriel Bonin Mongi Sghaier Seema Purushothaman Stefan Sieber Martin K. van Ittersum Floor Brouwer 《Land use policy》2011
For stimulating sustainable development in developing countries, land use patterns and land use changes are considered critical, and therefore effective and efficient land use policies are needed. In this paper we present a methodological framework that has been developed in a joint European and developing countries project (LUPIS – Land Use Policies and Sustainable Development in Developing Countries), to assess the impact of land use policies on sustainable development in developing countries. An illustrative application is presented for a case study in China, where water pollution due to agriculture in Taihu Basin is a major problem. 相似文献
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When land parcel boundaries are surveyed for purposes of registration in most southern African countries, the cadastral survey records and diagrams prepared have to be examined and approved by the Surveyor General first before they can be registered in the Deeds Registries. For such records to be approved, their quality must conform to requirements stipulated in relevant acts and regulations. Where regulatory requirements are not met, the records are rejected and returned for corrections and resubmission. From a cross-organizational context, poor quality documents lodged upstream have the effect of congesting examination processes downstream as records are rejected and returned backwards due to quality failure. The paper proposes a quality performance measurement model to analyze quality performance in land administration work processes. The developed model is tested on 2 survey examination and approval sites and 3 deeds registration sites in Namibia, Zimbabwe and South Africa. Based on below expected quality results obtained at one of the sites, a root cause analysis was conducted to establish recurring and underlying causal factors upon which quality improvement strategies can be built on. 相似文献
167.
Sustainable technology development implies large changes in technological systems. The illustrative process ‘hydrogen fuel cell in a boat’ is used here as an example of a learning process concerning a transition towards a hydrogen economy. Theoretically the concepts of constructive technology assessment, back-casting and social niche management are combined in this approach. 相似文献
168.
Simon van Norden 《Journal of Applied Econometrics》1996,11(3):219-251
This paper develops a new test for speculative bubbles, which is applied to data for the Japanese yen, the German mark and the Canadian dollar exchange rates from 1977 to 1991. The test assumes that bubbles display a particular kind of regime-switching behaviour, which is shown to imply coefficient restrictions on a simple switching-regression model of exchange rate innovations. Test results are sensitive to the specification of exchange rate fundamentals and other factors. Evidence most consistent with the bubble hypothesis is found using an overshooting model of the Canadian dollar and a PPP model of the Japanese yen. 相似文献
169.
The cultural theory pioneered by Dame Mary Douglas has been tested with a range of research methods, but it has not yet been made subject to a ‘structured observation’. This method has been developed in psychology and management studies, and is especially useful for testing cultural theory’s prediction that fatalistic, hierarchical, egalitarian, and individualistic ways of perceiving and justifying tend to emerge in group debates about pressing social and environmental issues. We present the results of a structured observation of this prediction. Groups of high school students (aged 17–19) were asked for their opinions concerning three to five ‘wicked’ (i.e., highly complex) problems, and to discuss how to resolve them. Each utterance was coded according to the rationalities proposed by cultural theory. The results confirm cultural theory’s hypothesis that all four specific ways of defining, perceiving and resolving a wicked problem emerge when a number of people debate such an issue. We also discuss how Douglas’ cultural theory can be further developed and tested. Finally, we use our study to outline how the method of structured observation can contribute to political culture research in general. 相似文献
170.