宁波-舟山港马岙港区灌门狭口段航道设计

宁波-舟山港马岙港区位于舟山中部海域,其中灌门狭口段为该港区进港航道的主要限制段.该狭口段受两侧暗礁和架空线限制,航道水流流态复杂且航道转弯角度大,是舟山地区通航条件最为复杂的海域之一.通过参考国外规范和舟山地区通航经验,结合数模、船舶模拟、实船试验等方法优化炸礁平面布局,结合实测潮流资料优化船舶狭口段通航时机,合理利用电缆悬链线形式提高航道通航能力,给出了复杂岛礁水域的航道设计方法,可为类似工程提供参考.     

Evaluation of manatee habitat systems on the northwestern Florida coast

Abstract

Threats to the survival of West Indian manatees (Trichechus manatus) vary throughout their range so that protection of this endangered species requires careful planning on a regional and local basis. The importance and vulnerability of various components of manatee habitats in the Crystal River area of northwestern Florida were assessed, using an ordinal‐combination mapping technique similar to procedures practiced in urban and regional planning. Habitat components were mapped and evaluated in juxtaposition with relevant characteristics of human use of the area, to identify areas of existing and potential manatee/human conflicts in need of reconciliation. Areas evaluated as the most important manatee habitats within this region include Crystal Bay and River, Homosassa River, and the Suwannee River estuary. Existing overlap of human activities with important manatee habitats is most critical near the urban communities of Crystal River and, to a lesser degree, Homosassa Springs. The need for integration of this ecological information into coastal land‐use planning is discussed.     

Elastic response characteristics of a very large floating structure in waves moored inside a reef

 This article describes the results of hydraulic model tests of the elastic response of a very large floating structure (VLFS) moored inside a reef in an isolated island. The distributions of strains and vertical displacements due to the elastic response of the VLFS were measured. The response characteristics were strongly affected by deformed nonlinear waves inside the reef. A two-step analytical method to compute the elastic response of a VLFS is proposed, and its validity is verified using the results of the hydraulic model tests. Received: May 2, 2002 / Accepted: March 17, 2003 RID="*" ID="*" Address correspondence to: S. Shiraishi (shiraishi@pari.go.jp) Acknowledgment. This study was supported by the Program for Promotions of Fundamental Transport Technology Research from the Corporation for Advanced Transport and Technology (CATT).