Abstract：
Floods are one of the most frequent global natural hazards resulting in significant human and economic losses. Therefore, assessing and mapping flood hazard levels is essential to reduce the severity of future flood disasters. This study developed an integrated methodology to evaluate flood risk using an improved Analytic Hierarchy Process (AHP) and Entropy Weight (AHP-EW) method based on cosine similarity (COS-AHP-EW). This method has more scientific results because it combines subjective and objective information. The proposed method\'s viability was then tested in Wuhan, China. Fourteen flood-inducing indicators were identified for the flood hazard, vulnerability, and restorability index system, with the indicator weights calculated using the COS-AHP-EW. This study utilized the Jenks method to develop the Wuhan flood risk map. We observed that the very high risk and high-risk areas covered 2.43% and 11.54% of the total study area and were mainly distributed in the highest economic and urbanization development and low-permeability districts, respectively. The validation with the historical waterlogging points reflected the accuracy and reliability of the COS-AHP-EW. The superiority of the proposed method was further verified by comparing it with single-evaluation methods (AHP and Entropy Weight) and another combined weight method (combined AHP-EW based on ideal point theory, namely, Ideal-AHP-EW). The comparison results indicated that the COS-AHP-EW was more accurate at predicting the risk in flood-prone area. Flood risk maps generated using the COS-AHP-EW could be applied to improve flood risk assessments, and the proposed method could be extended to other study areas to provide reliable flood management information.
摘要：
洪水是最常见的全球自然灾害之一，造成重大的人类和经济损失。因此,评估和绘制洪水灾害水平对于降低未来洪水灾害的严重程度至关重要。本研究开发了一种基于余弦相似性（COS-AHP-EW）的改进的层次分析法（AHP）和熵权（AHP-EW）方法来评估洪水风险的综合方法。该方法结合了主观和客观信息，因此具有更科学的结果。然后在武汉测试了该方法的可行性，中国。确定了14项洪水灾害诱发指标,脆弱性,和可恢复性指标体系，指标权重使用COS-AHP-EW计算。本研究利用Jenks方法绘制了武汉洪水风险图。我们观察到极高风险区和高风险区分别占总研究区的2.43%和11.54%,主要分布在经济和城市化发展程度最高和低渗透区,分别。对历史积水点的验证反映了COS-AHP-EW的准确性和可靠性。通过与单一评价方法(AHP和熵权)和另一种组合权重方法(基于理想点理论的AHP-EW组合,即,理想的AHP-EW）。比较结果表明，COS-AHP-EW可以更准确地预测易发洪水地区的风险。使用COS-AHP-EW生成的洪水风险图可以用于改善洪水风险评估，所提出的方法可以扩展到其他研究领域，以提供可靠的洪水管理信息。
