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961.
Chesser RK Bondarkov M Baker RJ Wickliffe JK Rodgers BE 《Journal of environmental radioactivity》2004,71(2):147-157
Using data obtained from 435 radiation sampling stations in the Red Forest, 1.5 km W if the Chernobyl Nuclear Complex, we reconstructed the deposition pathway of the first plume released by the accident, Chernobyl's Western Trace. The dimensions and deposition rates of the plume remain sharply defined 15 years after the accident. Assuming a uniform particle distribution within the original cloud, we derived estimates of plume dimensions by applying geometric transformations to the coordinates at each sample point. Our derived estimates for the radioactive cloud accounted for 87% of the variation of radioactivity in this region. Results show a highly integrated bell-shaped cross-section of the cloud of radiation, approximately 660 m wide and 290 m high, traveling at a bearing of 264 degrees from reactor IV. Particle sizes within Chernobyl's Western Trace were within the most dangerous range for inhaled aerosols (2-5 microm). Therefore, reconstruction of the dispersion of such particles is critical for understanding the aftermath of nuclear and biological aerosol releases. 相似文献
962.
Land Evaluation for Maize Based on Fuzzy Set and Interpolation 总被引:1,自引:0,他引:1
The objective of this article is to apply fuzzy set and interpolation techniques for land suitability evaluation for maize in Northern Ghana. Land suitability indices were computed at point observations using the Semantic Import (SI) model, whereas spatial interpolation was carried out by block kriging. Interpolated land suitability shows a high correlation (R2 = 0.87) with observed maize yield at the village level. This indicates that land suitability is closely related to maize yield in the study area. Membership functions were further used to assess the degree of limitation of land characteristics to maize. Sixty percent of the data has membership functions ranging from 0.23 for ECEC to 1.00 for drainage. ECEC, organic C, and clay are the major constraints to maize yield. The use of the fuzzy technique is helpful for land suitability evaluation, especially in applications in which subtle differences in soil quality are of a major interest. Furthermore, the use of kriging that exploits spatial variability of data is useful in producing continuous land suitability maps and in estimating uncertainties associated with predicted land suitability indices. 相似文献
963.
K. Tybirk H. F. Alr?e P. Frederiksen 《Journal of Agricultural and Environmental Ethics》2004,17(3):221-222
Editorial Commentary
Editorial 相似文献964.
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This review of incentives to evacuate is meaningful largely in the context of planning for and managing the consequences of the impact of riverine floods. Of course, incentives do not constitute an emergency plan. At best, they should be seen as suggestions for structuring some elements of a plan. Furthermore, the enumeration of incentives presented here is meant to be suggestive rather than exhaustive. A primary objective of this paper has been to underscore the importance of advance planning in coping with hazards and to argue that, even though limited, existing research can be productively used in the planning process. The incentives described here are based upon or drawn from empirical research on people's performance under flood disaster conditions. This reflects the view that it is important to build emergency planning around people's known reaction patterns. Too often emergency plans which are administratively devised turn out to be based upon misconceptions of how people react (cf. Drabek and Stephenson, 1971, p. 202; Dynes et al., 1972, p. 31) and, therefore, potentially create more difficulties than they solve. One must be cautioned, however, that although our data indicate that people say they would support the idea of various evacuation incentives examined here, these are attitudinal data and not performance data. Thus, the real test of evacuation incentives lies in their implementation and in evaluation data on pilot programs which, unfortunately, do not presently exist. The outlook for the feasibility of developing and utilizing evacuation incentives appears to be positive, though, judging from responses to our interviews. In the final analysis, it would appear to be wise to develop emergency plans which guide and channel citizen actions into complementary and productive protection behavior patterns. The present discussion of incentives to evacuate is intended to encourage data-based emergency planning. 相似文献
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