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1.
This paper describes the creation of an environmentally conscious community group, the Great River Network, and the role that it has played in the remediation and restoration process as part of one of the Great Lakes environmental programs. Community engagement was initiated in the region as part of the Remedial Action Plan for the Area of Concern at Cornwall/Akwesasne/Massena within the Upper St. Lawrence River. The community group formalised as a network representing 50+ organisations in response to perceived inadequacies in the agency of the community to respond to new environmental concerns outside of the scope of the existing programs. As a grass-roots initiative, the Great River Network has successfully completed remediation and restoration actions of significant value to the environment. These include a series of river clean ups (>42 tonnes of garbage removed), fish habitat restoration, and addressing shoreline erosion issues. Success has been achieved through partnering with a range of organisations, including Indigenous, non-profit, governmental, Conservation Authorities, businesses and industry partners. The action-oriented approach showcases how remediation and restoration led by, and embedded in, the community can result in true revitalization. A simplified framework for adaptive management practices for remediation and restoration efforts that lead to revitalization, including knowledge translation, is proposed. This case study highlights the transformational opportunities that remediation and restoration initiatives can bring. In this instance, the process is intensely local and cooperative and lays the foundation for moving towards a collective impact approach for the region.  相似文献   
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In this paper, a reproduction of a swing‐up and a giant swing motion of underactuated robots based on technique of the horizontal bar gymnast is discussed with focusing on an equivalent center of mass (ECM) of underactuated robots and the gymnast. At first, the behaviors of the ECM of the gymnast (ECMG) are analyzed by using a motion capturing technique and an efficient motion of the ECMG for the swing‐up and for the giant swing motion are identified from analysis results, respectively. Next, a partial linearization method, which can realize that the ECM of the Acrobot (ECMA) replicates this efficient motion, is designed and reproduces the underactuated robots the swing‐up and giant swing motion like the gymnast. Finally, an effectiveness of the proposed controller is shown by numerical simulations.  相似文献   
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Presently, many wind turbine generators (WTGs) are connected to the power grid. While the penetration of wind power to the power system is increasing, FIT price is decreasing. Therefore, wind generation companies want to increase the electric power output from wind farms (WFs). In this article, we propose a control technique to reduce the influence of the wake by changing a power coefficient of each WTG in a WF for the purpose of improving electric power output of WFs. We showed the optimization technique of a power coefficient of each WTG and the effect of reducing the influence of the wake using measurement data from WFs. In addition, we formulated the wake effect as a function of distance between WTGs. We verified 1% improvement of generated energy in a year compared to the conventional control method by simulation. Furthermore, we quantified the improvement of generated energy output, using the distance between WTGs and the occurrence rate of the direction of the wind as a variable.  相似文献   
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以CFD数值计算和实验相结合的方法,对处于中国西南某多山地区陆上风电场的尾流特性进行研究,验证不同数值方法在复杂地形的适用性。首先采用2台激光雷达,测量目标风力机一个月内的自由来流风速和尾流廓线,在地形上坡加速效应下,不同大气稳定度下目标风力机的自由来流风速廓线均呈负梯度。然后分别采用经典致动盘和改进致动盘法,模拟目标风力机在主风向下的尾流发展。不同于只有风速与压降关系的经典致动盘法,改进致动盘法更考虑了叶片几何和气动参数(尺寸信息、攻角、桨距角、升阻力系数等)。通过与后置激光雷达尾流测试结果对比,这2种基于CFD技术的数值模拟方法,计算网格相同,计算时间相当,且均能较好地模拟因为复杂地形而引起的尾流偏转;其中改进致动盘的尾流形状与激光雷达相似,速度亏损也更接近激光雷达结果。因此,改进致动盘法更适合于复杂地形条件下风场模拟,较好平衡了计算的效率与精度。  相似文献   
6.
In an era of population ageing, the primary home is increasingly viewed as a personal resource that can perform a pension role in retirement. This article assesses the extent to which Australians aged 45 years and over withdraw housing equity through in situ mortgage equity withdrawal (MEW), downsizing and selling up. We find that the incidence of housing equity withdrawal has increased over the last decade despite a global financial crisis. MEW is the dominant form of equity release among those under pension age, while downsizing or selling up is more frequent among those above pension age. Downsizing and selling up are more likely to be prompted by adverse life events than MEW. Selling up is typically an option of last resort. Our findings offer insights into important debates around homeownership societies and the welfare role performed by owner-occupied housing in mid-to-late life.  相似文献   
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Beginning with a laboratory‐scale physical model, a scale‐up correlation for a pilot unit project was determined based on the analysis of dynamic similarity correlations involving the predominant phenomena of a dissolved air flotation (DAF) chamber. The implantation costs of pilot units require special strategies due to the lack of correlations of this type, as novel flotation methods have been considered strictly from an economic standpoint. With the aid of computational fluid dynamics and videos of microbubble and floc flow, inertia and gravity were identified as the predominant phenomena in a DAF chamber. The strategy described herein is simple and reduces the likelihood of future risks in scale‐up investments.  相似文献   
9.
A fast method is proposed for determining the oxygen gas‐liquid diffusion coefficient from measurements of the fluorescence quenching behind a bubble. The approach consists of capturing pictures of the concentration field at micro‐scale in the laminar bubble wake. The Gaussian concentration profiles measured in the wake are demonstrated to be systematically equivalent to an instantaneous plane diffusion case. The approach permits to accurately evaluate the gas‐liquid diffusivity in a very short time of around one second.  相似文献   
10.
为解决超差双翻斗式雨量传感器在检定校准时精细定量调测问题,尤其针对:在大小雨强(4mm/min和1mm/min)测试时超差值为一正一负,目前只能通过目测观察法并依靠经验对容量调节螺母和定位螺母进行调节,这存在着一定的盲目性并且成功率低。提出了一套检定流程并利用红外光电传感器和步进电机模块,实现了上翻斗和计量翻斗的左右斗的翻动数据的定量测量以及定位螺母和容量调节螺母的自动调节,并且可自动记录和上传检定数据到上位机。结果表明:本系统能有效地判定和解决翻斗翻动平衡和协调性问题,并可为业务人员积累检定数据以便后续分析处理。  相似文献   
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