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81.
Cameroon has been a keen participant in Reducing Emissions from Deforestation and Forest Degradation plus conservation, sustainable management of forests and enhancement of carbon stocks (REDD+) negotiations since 2005 and has engaged in activities to enhance the implementation of REDD+. This article reviews progress on REDD+ readiness in Cameroon based on a multiple REDD+ functions framework. Results show that some progress has been made in terms of planning and coordination, institutional development, and the development of some REDD+ projects. Absence of a legal framework, inadequate procedures for stakeholder participation, slow progress in the development of a national strategy, monitoring, reporting, and verification (MRV) challenges, and weak financing remain prominent constraints. Despite having one of the slowest REDD Readiness Preparation Proposal (R-PP) processes in the Congo Basin, stakeholders feel strong ownership because the R-PP was done almost entirely by Cameroonian experts. Some opportunities for improving REDD+ can be considered going forward, including the establishment of procedures for a broader participatory process, speeding up the operationalization of the National Observatory on Climate Change, making use of the ongoing forestry law reform, consideration of a carbon concessions concept, tapping from international initiatives to build on MRV, and improving benefit sharing and financing through the development of an appropriate and decentralized mechanism. Enhancing these opportunities is fundamental for successful REDD+ implementation in Cameroon.Policy relevanceThis article offers a new multidimensional approach to assessing the REDD+ readiness process in Cameroon. This critical assessment, which is done using six key functions, provides an opportunity for enhanced understanding of the process by policy makers, decision makers, and professionals with a view to enabling improvements in the readiness process. Furthermore, the article proffers a series of opportunities that the government and other relevant stakeholders can capitalize on to overcome current hurdles affecting the REDD+ readiness process. It is hoped that policy makers driving the REDD+ process in Cameroon will be able to incorporate the findings of this research into their strategic policy, formulated to advance the REDD+ readiness process. More importantly, it is hoped that the multidimensional framework applied in this study could be useful for assessing REDD+ in similar contexts in the Congo Basin. 相似文献
82.
Reducing model complexity for explanation and prediction 总被引:1,自引:1,他引:1
Numerical models can be useful for explaining poorly understood phenomena or for reliable quantitative predictions. When modeling a multi-scale system, a ‘top-down’ approach—basing models on emergent variables and interactions, rather than explicitly on the much faster and smaller scale processes that give rise to them—facilitates both goals. Parameterizations representing emergent interactions range from highly simplified and abstracted to more quantitatively accurate. Empirically based large-scale parameterizations lead more reliably to accurate large-scale behavior than do parameterizations of much smaller scale processes. Conversely, purposefully simplified representations of model interactions can enhance a model's utility for explanation, clarifying the key feedbacks leading to an enigmatic behavior. For such potential insights to be relevant, the interactions in the model need to correspond to those in the ‘real’ system in some straightforward way. Such a correspondence usually holds for models constructed for predictive purposes, although this is not a requirement. The goals motivating a modeling endeavor help determine the most appropriate modeling strategies, as well as the most appropriate criteria for judging model usefulness. 相似文献
83.
基于多重互相关函数分析剪切波速 总被引:1,自引:0,他引:1
介绍了一种提高单孔法剪切波速测量精度的新方法-多重互相关函数法。考虑到判断场地剪切波到时差的困难,提出了用多重互相关函数来求得两剪切波的到时差。互相关分析可求取两相似信号的到时差,但当两信号相似性比较差时,所求得到时差的误差较大;自相关函数本身可进行多重自相关分析,互相关函数结合多重自相关函数后,也可以进行多重互相关分析来求取两相似信号的到时差。试验表明:相比互相关函数,多重互相关函数可改善触发信号和井中三分向探头输出信号的相似性及更好地抑制噪声,因此能更精确地计算出触发信号和井中三分向探头输出信号的的到时差。基于此原理设计了剪切波波速的测试系统,此系统能自动分析出测点的剪切波速和形成完整的报告。 相似文献
84.
目前没有规范给出串锚的水平承载力计算公式,为了利用有限元法研究串锚水平承载力特性,采用相关理论计算以及室内试验的方法来验证有限元法模拟计算的可靠性。实践证明,有限元法具有较高的计算精度。利用有限元分析软件ABAQUS建立了串锚-土体模型,模拟串锚在水平荷载作用下破坏过程,研究了串锚在水平荷载作用下破坏机理,从而得到了串锚水平承载力特性。在相同的工况条件下,串锚的水平承载力与其锚链长度有关,在一定范围内,增加锚链的长度可以提高串锚的水平承载力;串锚的水平承载力不是相应的单个锚的水平承载力相加,其水平承载力小于相应的单个锚水平承载力之和,在进行串锚水平承载力设计计算时应给与相应的考虑。 相似文献
85.
Toward micro-scale spatial modeling of gentrification 总被引:1,自引:0,他引:1
David O'Sullivan 《Journal of Geographical Systems》2002,4(3):251-274
A simple preliminary model of gentrification is presented. The model is based on an irregular cellular automaton architecture
drawing on the concept of proximal space, which is well suited to the spatial externalities present in housing markets at
the local scale. The rent gap hypothesis on which the model's cell transition rules are based is discussed. The model's transition
rules are described in detail. Practical difficulties in configuring and initializing the model are described and its typical
behavior reported. Prospects for further development of the model are discussed. The current model structure, while inadequate,
is well suited to further elaboration and the incorporation of other interesting and relevant effects.
Received: 1 November 2001 / Accepted: 12 April 2002
Town centres data were made available by kind permission of the UK Department of the Environment, Transport and the Regions. 相似文献
86.
87.
Comparisons of Simulations of Soil Moisture Variations in the Yellow River Basin Driven by Various Atmospheric Forcing Data Sets 总被引:3,自引:0,他引:3
Based on station observations, The European Centre for Medium-Range Weather Forecasts reanalysis (ERA40), the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis and Princeton University's global meteorological forcing data set (Princeton), four atmospheric forcing fields were constructed for use in driving the Community Land Model version 3.5 (CLM3.5). Simulated soil moisture content throughout the period 1951-2000 in the Yellow River basin was vali... 相似文献
88.
MichaelO'Rourke VikramGadicherla TarekAbdoun 《地震工程与工程振动(英文版)》2005,4(1):69-73
A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI‘s 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics, (diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2 and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results. 相似文献
89.
利用常规观测资料分析2009-2011年天津地区33次局地暴雨天气过程的影响系统。对局地暴雨天气发生前的大气环境物理参数进行统计,对比不同影响系统下预报着眼点的差异。结果表明:天津局地暴雨主要发生在蒙古冷涡、东北冷涡、高空槽前以及高空槽后四种天气系统的影响下。蒙古冷涡系统下应以整层良好的水汽和涡旋系统东南象限深厚的辐合上升运动为着眼点;而东北冷涡系统下则需关注低层水汽条件充沛和中层强烈的辐合抬升;高空槽系统下在动力、水汽以及能量条件配合较为均衡;而槽后型系统影响下若发生局地暴雨,各种强对流参数特征则最为显著。在此基础上,通过典型局地暴雨过程对强降水落区进行诊断表明,天津构造加密探空由于充分考虑了近地面的温湿风特征,计算所得的可降水量、对流有效位能以及地面至3km高度的垂直风切变对局地暴雨落区具有良好的指示性。同时,个例研究也表明TJ-WRF对局地暴雨天气过程有较好的预报能力,综合应用模式物理量结果能较好地预报局地暴雨落区。 相似文献
90.
The random model of drainage basin composition is founded on the assumptions that (a) natural channels are topologically random in the absence of geological controls and (b) for channel networks developed in similar environments, the exterior and interior link lengths are independent random variables with a common distribution for each type. The effectiveness of this model in estimating the values of geomorphic variables and in explaining and predicting geomorphic relationships is illustrated by several examples. The data required for these examples were obtained from map studies of 30 channel networks, comprising a total of about 8700 links, in eastern Kentucky. A common factor in the success of all three applications of the model is the way in which the planimetric features of drainage basins are determined by their underlying topologic structure. 相似文献