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991.
In those coastal communities where the most seaward strip of mainland consists of dunes, these dunes often serve as a flexible sea defence. In addition, this strip offers large potential for housing and commercial enterprises. Unfortunately, due to severe storm surges part of this strip (the erosion zone) is subject to erosion, and as a result of which any buildings or infrastructure located here, are destroyed. Therefore, as we will illustrate in this paper, a building policy for this zone should reflect a compromise between two opposite interests: exploitation of the existing potential and, prevention of an unacceptable high risk due to erosion. Accordingly, the authors have developed a framework for such a building policy on the basis of which the desirability of various different types of investments and the location within the erosion zone of such investments can be determined. The examples that are used to illustrate this framework in this paper are limited to experiences in The Netherlands as relevant data and experiences are available and relatively easy accessible here. Nevertheless, the approach as is described is generic and applicable worldwide suggesting that the discovered unused potential for exploitation is not just limited to The Netherlands. 相似文献
992.
993.
介绍了通过布设足够密度且分布均匀的GPS水准联测点,建立庄河市辖区4086 km2的高精度、高分辨率的似大地水准面数学模型的原理和方法. 相似文献
994.
This paper presents a simple nonlinear data-based modelling approach for predicting the beach profile volume at Duck, North Carolina, USA. The state-dependent parameter form of the general transfer function (SDP TF) model is used to describe nonlinearity influencing these morphological data in two case examples. Case 1 investigates the nonlinearity associated with the dependency of wave forcing on the preceding beach volume. Case 2 investigates the ability to model the variables within the well-known diffusion equation for beach volume using this data-based approach. The results of this study show that the SDP TF approach can be used successfully to develop statistically robust models for describing nonlinearity in beach morphological systems. Furthermore, these models are shown to predict the beach volumes over both short (1 month ahead) and long (2 years ahead) time periods, and thus show great potential for practical applications in coastal zone management and engineering. 相似文献
995.
This paper analyses the extent to which specialisation gains can be achieved by liberalising access to fishing quotas within the European Union (EU). Fishing quotas are today exchanged between EU member states at a rate of 4% of total turnover in EU fisheries. Germany, Belgium, Denmark and the Netherlands are the most active. Only one fourth of these exchanges are permanent. With the management systems in EU fisheries differing among countries, comparative advantages in fisheries exist in member states with the best management practices. Hence, although positive but small specialisation gains exist in EU fisheries today, these gains might potentially be increased by liberalising access to fishing quotas and allowing transferability of quotas between individuals from different countries on a permanent basis. Increasing the gains might, however, affect relative stability. 相似文献
996.
改进型经验正交函数海洋声速剖面预报方法 总被引:1,自引:0,他引:1
鉴于深海温跃层以下往往声速值缺乏,声速剖面不完整的原因,提出一种声速剖面的预报方法:在传统经验正交函数预报法基础上,首先改进协方差矩阵的求解方法,将原始数据的空间信息和时间信息有效地融合到协方差矩阵中,通过由大量实测数据统计得出的时间函数的经验公式,得到合成剖面,将二者结合,把不完整剖面垂直向下延拓到海底,较为有效地解决了传统方法求解协方差矩阵和时间函数较粗糙的问题,给出了完整的海洋声速剖面的准确预报.实测数据检验结果表明,改进方法的预报精度比传统方法有了很大提高. 相似文献
997.
?????????????μ????????μ???????????÷?????????????е????????????е???С??????????????????????????????????????????????????????????ι???????????????÷?????????С? 相似文献
998.
999.
�����Ƚ����Ƶ�ֱ����С������Բ��� 总被引:3,自引:0,他引:3
?????????????????????????????????????????????????????????????????????????伸?β????????????????????????????????????????????????????????????????????????С????????????,??Matlab?????????????????????????????????????????????????????????????????????????????Ч???á??????? 相似文献
1000.
????????????????????????????Σ?????????????????????????????????趨???????????м???????е???????????????????ó?????????????????????????????????????????????????????????????????????????????淽??????????????????????????????????????????????????????????????????????????????淽???????????????????????????????????÷??????????Ч??? 相似文献