The graduation project starts from the attention and research to the dynamic water level change in coastal area in North Sea, and by analysising the potential flooding risks, climate-sensitive mudflat, and the relationship between regional ecosystem and local people, the observation to changing coastal landscape are emphasised, to rethink how to reuse the leftover human space to reflect the changing ecological environment, emphasing people's bioregionalism awareness. By Redefining the meanings of the fortification heritage, the meanings of the Grain tower, defencing not only the national territory but defence for the territory defined by the whole nature; not only record the history, but measure the changing nature through time. Key words: Soft edge between sea and land , fortificaton heritage architecture, tidal mudflat, changing horizon, bioregionalism, changing ecological environment

The vacuum interrupter is used as the key component of an active DCCB due to its excellent interruption and dielectric recovery characteristics after current zero. The vacuum interrupter can only interrupt the fault currents below the limitation of a critical di/dt and TIV, otherwise it causes a reignition and the interruption failure. In this paper, a detailed active injection DC CB model is developed, considering operation delay of switches, parasitic parameters of switches and thorough control logic. The limitation dielectric strength between the vacuum gap is defined by the cold break down voltage. Based on the numerical modelling, investigation will be performed to see the performance of DC CB with a failure interruption on the first current zero. The simulation results can help to optimize the injection circuit parameters when DC CB has a failure on the first current zero and has to interrupt in the next current zeros. This algorithm will consider predefined threshold of di/dt, chopping current and variable operation time in different scenarios.@en