中文摘要：

首先对同一禀赋的50多个沿海城市进行了研究，发现其经济差距非常大；部分沿海城市虽然具有良好的港口、交通、环境等优势条件，但其发展却远不如相邻的周边内陆城市，出现了典型的“阴影”现象。其次，以日照市为例，在挖掘其优势条件与滞后效应矛盾的基础上，深入剖析了制约其发展的各种内外部因素。最后，根据这些制约因素提出了相应的发展策略，以期促使日照市尽快摆脱“阴影”现象。

英文摘要：

More than fifty cities with same coastal advantages have been analyzed in this paper at first. It finds that the difference of economic development between them is very large, and even though part of those cities has much predominance in port, traffic, environment etc. , those development lags behind greatly than the inland cities around, causing the typical ＂shadowy＂ phenomenon. Secondly, taking Rizhao. City for example, it makes a deep analysis to the inner and exterior factors which restrict its development based on the discussion of its paradox on the dominance conditions and lagging effect. Finally, the corresponding development strategies are put forward according to the factors in order to get rid of ＂shadowy＂ phenomenon.