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经济的不断发展造成了极大的环境污染,需要人们用科学的手段对经济发展和造成的环境污染之间的关系进行客观判断.采用主成分分析法、格兰杰因果检验以及基于VAR的脉冲响应函数对青岛市的经济发展与环境污染二者间关系进行分析,结果发现由于环境承载力的存在,经济增长造成环境污染在很大程度上受到时滞的影响,经济增长引发环境问题是渐进的、长期的,所以在发展经济时不能只顾眼前利益而忽视对环境的长期影响,要注重可持续发展.  相似文献
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The traditional governing equations for sway–yaw maneuvering motion are a set of ordinary differential equations with constant coefficients. But, as is well known, integro–differential equations with impulse response functions are more strict governing equations that can handle the frequency dependence of hydrodynamic forces.In this paper, the two types of equation are compared and used to calculate the 10°–10° zig-zag maneuver in waves. Differences between the solutions are discussed.  相似文献
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Monitoring offshore platforms, long span bridges, high rise buildings, TV towers and other similar structures is essential for ensuring their safety in service. Continuous monitoring assumes even greater significance in the case of offshore platforms, which are highly susceptible to damage due to the corrosive environment and the continuous action of waves. Also, since a major part of the structure is under water and covered by marine growth, even a trained diver cannot easily detect damage in the structure. In the present work, vibration criterion is adopted for structural monitoring of jacket platforms. Artificial excitation of these structures is not always practicable and ambient excitation due to wind and waves may not be sufficient for collecting the required vibration data. Alternate methods can be adopted for the same purpose, for example, the application of an impact or a sudden relaxation of an applied force for exciting the structure. For jacket platforms, impact can be applied by gently pushing the structure at the fender while relaxation can be accomplished by pulling the structure and then suddenly releasing it using a tug or a supply vessel in both cases. The present study is an experimental investigation on a laboratory model of a jacket platform, for exploring the feasibility of adapting vibration responses due to impulse and relaxation, for structural monitoring. Effects of damage in six members of the platform as well as changes in deck masses were studied. A finite element model of the structure was used to analyze all the cases for comparison of the results as well as system identification. A data acquisition and analysis procedure for obtaining the response signatures of the platform due to the impulse and relaxation procedure was also developed for possible adoption in on-line monitoring of offshore platforms. From the study, it has been concluded that both impulse and relaxation responses are useful tools for monitoring offshore jacket platforms. The present work forms the basis for the development of an automated, on-line monitoring system for offshore platforms, using neural networks.  相似文献
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本文以中国海洋经济为研究对象,基于面板回归方法及脉冲响应分析,对北部、东部和南部海洋经济带的海域使用对海洋经济的影响关系开展实证研究,选取 2001-2015年填海造地、构筑物、围海、开放式和其他用海方式的海域使用面积 为被解释变量,以同期人均 GOP为解释变量,构建计量经济模型并进行实证分析,研究结果发现:淤模型拟合效果较好,采用面板模型和脉冲响应来分析海域使用与海洋经济之间的关系具有较强的适用性;于三大海洋经济带海洋经济增长与海域使用之间的关系无论是在空间区域上还是在时间序列上差异性特征都很明显。  相似文献
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狄乾斌  周慧 《海洋通报》2019,(5):499-507
在分析人口发展与海洋经济互动关系的基本理论上,构建综合评价指标体系,运用耦合协调度模型和脉冲响应函数对2000-2015年中国沿海11省市的人口发展与海洋经济发展进行测算,实证结果表明:①人口发展与海洋经济发展水平整体上波动上升,各沿海省市的经济发展水平差异明显;②人口发展与海洋经济之间的耦合协调度波动上升,研究期内天津市、上海市、广东省均处于高度耦合协调,福建省、山东省耦合协调度提高明显,发展趋势较好;③人口发展对海洋经济的响应较弱,海洋经济对人口发展的响应较强,沿海各省市人口发展与海洋经济之间的相互响应关系有待加强。  相似文献
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