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161.
Willingness to Pay (WTP), Willingness to Work (WTW) and Willingness to Accept Compensation (WTA) are the three quantitative criteria for assessing local ecological asset values for the social aspects of ecosystem services and residents’ willingness to contribute to and receive compensation for tourism ecology. The objectives of this study are to estimate the residents’ willingness to pay, work and accept compensation for conservation at Sanjiangyuan National Park, and to analyze the relationship between residents’ attitude towards tourism ecology and the ecological assets of the National Park based on a standard questionnaire survey. The dichotomous choice Contingent Valuation Method (CVM) was employed to determine the willingness. The survey conducted in 2018 collected WTP, WTW, WTA, socio-demFographical information, social trust and resident perceptions toward tourism impacts and relevant management strategies from 244 residents in two counties. Based on generalized linear modeling, income and education level are important for residents’ WTP and WTA, but other social characteristics, such as gender and age, do not have significant effects. The social trust is found to be a significant factor on residents’ willingness, despite the limitation on education level. Also, government funding is associated with residents’ inclination to WTP, WTW and WTA, but the support levels differ among the two counties due to geographical and social heterogeneities. The estimated WTP, WTW and WTA for the Sanjiangyuan National Park in 2018 were 1.2448×10 7 yuan, 1.247×10 6 hours and 2.3232×10 7 yuan yr -1 based on the survey and published demographics. This study, for the first time, estimates the WTP, WTW and WTA for the Sanjiangyuan National Park and informs ecological conservation managers and policy makers. Ultimately, to maintain the long-term benefits arising from sustainable development, compensation should be specifically tailored and site-dependent, and development measures based on local resources should be adopted by governments to actively support eco-tourism activities. 相似文献
162.
Ecosystem services (ES) is an important approach to biodiversity protection in political rhetoric and policy practice, but it is also highly contested. This paper analyzes the introduction of ES in Swedish environmental policy and how it is contested by key stakeholders and discusses its implications for biodiversity governance. The results show that although ES is widely accepted on an abstract and conceptual level, critical features and functions are highly contested. These primarily concern the valuation of nature, appropriateness of different policy instruments, and institutional structures. The paper concludes that while the controversy surrounding ES fills an important role by reinvigorating debate and stimulating reflections on biodiversity loss, it also illustrates how ES is used to further particular values and beliefs and to challenge traditional biodiversity-protecting strategies. Understanding these policy controversies is central to addressing the challenges of transforming the promises of ES into practical policies. 相似文献
163.
This paper describes the development of a numerical model for compensation grouting which is a useful technique for the protection of surface structures from the potentially damaging movements arising from tunnel construction. Pipes are inserted into the ground between the tunnel and the overlaying structure from an access shaft. Buildings on the surface are instrumented and movements are carefully monitored. Once the deformations exceed a certain Trigger Level, grout is injected into the ground to prevent damage. In the finite element model described here, compensation grouting is modelled by applying an internal pressure to zero‐thickness interface elements embedded in the mesh. An ‘observational algorithm’ is used, where the deformations of the surface are monitored and used to control the injection process. Example analyses of compensation grouting are given for three‐dimensional tunnel construction underneath a greenfield site. Different strategies are used to control the injection process and their effectiveness in preventing surface movement is assessed. The numerical model is shown to replicate general behaviour expected in the field and is capable of modelling the control of ground surface movements at a greenfield site. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
164.
提出了一种蒸散发实测方法——三筒补偿蒸渗仪法,可以在不干扰芦苇生长状态的原形条件下,直接测算出芦苇沼泽蒸散耗水量和水面蒸发量。扎龙湿地2004、2005两年的实测结果表明,5月中旬至10月中旬间的芦苇带平均蒸散量(AET)为812.1 mm,水面蒸发量(Ew)为433.9 mm;芦苇沼泽蒸散耗水量最大值发生在6、7月份,而水面蒸发量最大值出现在5月份;各月的AET/Ew比率变化明显,平均值为1.87。还根据实测数据建立了扎龙芦苇沼泽蒸散发的多元回归模型,可为湿地水资源规划和管理服务。 相似文献
165.
166.
通过对地震勘探仪器的主要技术性能的详细分析可以看出,无论是集中式数字地震仪还是24位Δ-∑A/D型遥测地震仪,都还记录不到大动态、高主频、宽频带的地震反射波,它们记录的中深层地震反射信号的瞬时动态范围均在60 dB左右.本文以水平层状介质的吸收衰减特性为依据,给出了智能程控型前置放大器和频谱均衡滤波器的数学模型.用智能程控型前置放大器补偿由于球面扩散所造成的振幅衰减;用频谱均衡滤波器补偿由于地层吸收所造成的振幅衰减.按此设计方案,研制真正具有大瞬时动态和高频提升功能的地震仪,对高分辨率地震勘探技术的进一步发展具有重要意义. 相似文献
167.
168.
This paper presents the implementation details of a real‐time pseudodynamic test system that adopts an implicit time integration scheme. The basic configuration of the system is presented. Physical tests were conducted to evaluate the performance of the system and validate a theoretical system model that incorporates the dynamics and nonlinearity of a test structure and servo‐hydraulic actuators, control algorithm, actuator delay compensation methods, and the flexibility of an actuator reaction system. The robustness and accuracy of the computational scheme under displacement control errors and severe structural softening are examined with numerical simulations using the model. Different delay compensation schemes have been implemented and compared. One of the schemes also compensates for the deformation of an actuator reaction system. It has been shown that the test method is able to attain a good performance in terms of numerical stability and accuracy. However, it has been shown that test results obtained with this method can underestimate the inelastic displacement drift when severe strain softening develops in a test structure. This can be attributed to the fact that the numerical damping effect introduced by convergence errors becomes more significant as a structure softens. In a real‐time test, a significant portion of the convergence errors is caused by the time delay in actuator response. Hence, a softening structure demands higher precision in displacement control. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
169.
Parker快速富氏变换反演单一密度界面存在两方面问题:一是求解目标界面重力异常难度较大;二是受正演速度及反演参量维数的限制,不能对界面进行精细划分.拟神经网络BP算法的引入,首先解决了快速三维正演问题,又突破了反演参量维数的限制,实现快速收敛,有效解决两个或多个密度界面的反演问题.在实际应用中,先用密度“补偿法”正演求取剩余生力异常,然后利用拟神经网络BP算法同时反演两个二维密度界面,拟合求得两个界面的深度异常,在此基础上预测煤田. 相似文献
170.