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101.
This paper offers a systematic analysis of the concepts and contexts that frame the climate-smart agriculture (CSA) discourse in the academic and policy literature. Documents (n?=?113) related to CSA and published in peer-reviewed journals, books, working papers, and scientific reports from 2004 to 2016 were reviewed. Three key trends emerged from the analysis: studies are biased towards global policy agendas; research focuses on scientific and technical issues; and the integration of mitigation, adaptation, and food security (the three pillars of CSA) is becoming a popular scholarly solution. Findings suggest that CSA is a fairly new concept used to describe a range of adaptation and mitigation practices without a specific set of criteria. Although CSA is often framed around the three pillars, the underlying issues constructing the discourse differ at global, developing, and developed country scales. Although there is increasing research on developing countries, particularly in relation to how CSA can transform smallholder agriculture, there is a paucity of research documenting the experiences from developed countries. The findings suggest that research on CSA needs to move beyond solely focussing on scientific approaches and only in certain geographical contexts. If CSA is to be applicable for farmers across the globe, then cross-disciplinary research that is underpinned by broad socio-economic and political contexts is essential to understand how differences in narratives might affect implementation on-the-ground in both developing and developed countries.POLICY RELEVANCEAlthough policy makers are increasingly supportive of the climate-smart agriculture (CSA) approach, the rhetoric has largely been developed on the basis of scientific and technical arguments. The political implications of varying perspectives have resulted in a growing divide between how developing and developed countries frame solutions to the impacts of climate change on agriculture under the 2015 Paris Agreement. Different framings are part of the explanation for why the scope of CSA is being rethought, with the scientific community redirecting attention to seeking a separate work programme under the United Nations Framework Convention on Climate Change (UNFCCC). The current policy framing of CSA will give no new policy direction unless it grounds itself in the smallholder farmer and civil society contexts. 相似文献
102.
P. K. Pal W. J. Prakash P. K. Thapliyal C. M. Kishtawal 《Meteorology and Atmospheric Physics》1999,71(3-4):157-168
Summary ?A methodology has been developed to assimilate satellite-measured rainfall during the initial phase of model integration
for extended range monsoon prediction. The vertical profiles of latent heating corresponding to different rain rates have
been derived from the model statistics. These heating rates have been assimilated through nudging in the thermodynamics equation
of the model. This procedure of assimilating observed heating has corrected the simulation of heating location in the model
and consequently removed the anomalous sinking motion over Indian landmass. With the correction of vertical circulation, both
mean July rainfall over India and the distribution have improved. Interannual variability has been brought out for the years
1987 and 1988. In view of the availability of rainfall profile from Tropical Rain Measuring Mission (TRMM) there is a scope
of adopting this method of assimilating observed rainfall, for extended range monsoon prediction.
Received February 12, 1999/Revised May 4, 1999 相似文献
103.
Forecasting weather parameters such as temperature and pressure with a reasonable degree of accuracy three hours ahead of
the scheduled departure of an aircraft helps economic and efficient planning of aircraft operations. However, these two parameters
exhibit a high degree of persistency and have nonstationary mean and variance at sub-periods (i.e. at 0000, 0300, 0600,…,
2100UTC). Hence these series have been standardised (to have mean 0 and variance 1) and thereafter seasonal differenced (lag
8) to achieve almost near stationarity. An attempt has been made to fit the standardised and seasonal differenced series of
Chennai (a coastal station) and Trichy (an inland station) airport into an Auto Regressive (AR) process. The model coefficients
have been estimated based on adaptive filter algorithm which uses the method of convergence by the steepest descent. The models
were tested with an independent data set and diagnostic checks were made on the residual error series. An independent estimation
of fractal dimension has also been made in this study to conform the number parameters used in the AR processes. The models
contemplated in this study are parsimonious and can be used to forecast surface temperature and pressure. 相似文献
104.
The disturbed state concept (DSC) model, and a new and simplified procedure for unloading and reloading behavior are implemented in a nonlinear finite element procedure for dynamic analysis for coupled response of saturated porous materials. The DSC model is used to characterize the cyclic behavior of saturated clays and clay–steel interfaces. In the DSC, the relative intact (RI) behavior is characterized by using the hierarchical single surface (HISS) plasticity model; and the fully adjusted (FA) behavior is modeled by using the critical state concept. The DSC model is validated with respect to laboratory triaxial tests for clay and shear tests for clay‐steel interfaces. The computer procedure is used to predict field behavior of an instrumented pile subjected to cyclic loading. The predictions provide very good correlation with the field data. They also yield improved results compared to those from a HISS model with anisotropic hardening, partly because the DSC model allows for degradation or softening and interface response. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
105.
106.
The grid DEM(digital elevation model) generation can be from any of a number of sources:for instance,analogue to digital conversion of contour maps followed by application of the TIN model,or direct elevation point modelling via digital photogrammetry applied to airborne images or satellite images.Currently,apart from the deployment of point-clouds from LiDAR data acquisition,the generally favoured approach refers to applications of digital photogrammetry.One of the most important steps in such deployment i... 相似文献
107.
Astronomy Reports - Though accurate laboratory studies of malononitrile (CH2(CN)2), a dinitrile molecule, have been carried out from time to time, and it has large electric dipole moment $$\mu =... 相似文献
108.
Successful numerical simulation of geosynthetic-reinforced earth structures depends on selecting proper constitutive models for soils, geosynthetics and soil–geosynthetic interfaces. Many constitutive models are available for modelling soils and geosynthetics. However, constitutive models for soil–geosynthetic interfaces which can capture most of the important characteristics of interface response are not readily available. In this paper, an elasto-plastic constitutive model based on the disturbed state concept (DSC) for geosynthetic–soil interfaces has been presented. The proposed model is capable of capturing most of the important characteristics of interface response, such as dilation, hardening and softening. The behaviour of interfaces under the direct shear test has been predicted by the model. The present model has been implemented in the finite element procedure in association with the thin-layer element. Five pull-out tests with two different geogrids have been simulated numerically using FEM. For the calibration of the constitutive models used in FEM, the standard laboratory tests used are: (1) triaxial tests for the sand, (2) direct shear tests for the interfaces and (3) axial tension tests for the geogrids. The results of the finite element simulations of pull-out tests agree well with the test data. The proposed model can be used for the stress-deformation study of geosynthetic-reinforced embankments through numerical simulation. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
109.
110.
A smoothed ANOVA model for multivariate ecological regression 总被引:3,自引:3,他引:0
Marc Marí-Dell’Olmo Miguel A. Martinez-Beneito Mercè Gotsens Laia Palència 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(3):695-706
Smoothed analysis of variance (SANOVA) has recently been proposed for carrying out disease mapping. The main advantage of this approach is its conceptual simplicity and ease of interpretation. Moreover, it allows us to fix the combination of diseases of particular interest in advance and to make specific inferences about them. In this paper we propose a reformulation of SANOVA in the context of ecological regression studies. This proposal considers the introduction in a non-parametric way of one (or several) covariate(s) into the model, explaining some pre-specified combinations of the outcome variables. In addition, random effects are also incorporated in order to model geographical variation in the combinations of outcome variables not explained by the covariate. Lastly, the model permits the decomposition of the variance in the set of outcome variables into different orthogonal components, quantifying the contribution of every one of them. The proposed model is applied to the geographical analysis of mortality due to malignant stomach neoplasm among women resident in the city of Barcelona (Spain). The available outcome variables are deaths grouped into two time periods, and a socioeconomic deprivation index is included as a covariate. The model has been implemented through INLA, a novel inference tool for Bayesian statistics. 相似文献