Landscape elements such as:mountains, vegetation, water, though natural, but it can be handled manually by a man-madefeatures to be shown;
景观要素如：山体、植被、水尽管是自然的，但它可以通过人工方式处理出人为所要表现的特征；
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It is a beautiful city in its own right, but the wonderful range of both man-made and natural features provides many exciting contrasts and unexpected highlights.
How to analyse the measured stress wave signal for an oil leakage monitoring system to get the features and the modes of manmade leakages is the key problem for accurate detection.