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1.
The main objective of this paper it to model the dynamic relationship between global averaged measures of Total Radiative Forcing (RTF) and surface temperature, measured by the Global Temperature Anomaly (GTA), and then use this model to forecast the GTA. The analysis utilizes the Data-Based Mechanistic (DBM) approach to the modelling and forecasting where, in this application, the unobserved component model includes a novel hybrid Box-Jenkins stochastic model in which the relationship between RTF and GTA is based on a continuous time transfer function (differential equation) model. This model then provides the basis for short term, inter-annual to decadal, forecasting of the GTA, using a transfer function form of the Kalman Filter, which produces a good prediction of the ‘pause’ or ‘levelling’ in the temperature rise over the period 2000 to 2011. This derives in part from the effects of a quasi-periodic component that is modelled and forecast by a Dynamic Harmonic Regression (DHR) relationship and is shown to be correlated with the Atlantic Multidecadal Oscillation (AMO) index.  相似文献   
2.
In 2015, Swiss voters had the opportunity to impose a tax on the super rich in a popular vote and thereby fund a redistributive policy. However, a large majority voted against its seemingly obvious self-interest and rejected the tax. We propose an explanation for this puzzling outcome, bridging the usually separate behavioralist and institutionalist perspectives on the politics of inequality. We start from the observation that political economy tends to neglect processes of preference formation. Theorising preferences as socially constructed, we show that interest groups played a major role in shaping the outcome of the vote. Business frames were multiplied through allied parties and the media and had a major impact on individual voting behaviour. In addition, we demonstrate that interest groups representing business interests derive the content of their communication from business’s structurally privileged position in the capitalist economy. Specifically, creating uncertainty about possible perverse effects of government policies on jobs and growth is a powerful tool to undermine popular support. Frames based on this structural power ultimately explain why the Swiss refrained from ‘soaking the rich.’  相似文献   
3.
Sustainable Public Procurement is an integral part of sustainable development because of ever increasing government expenditures. Most of the developing countries lack the required infrastructure which may support public sector sustainability. The aim of this study is to assess the critical factors which resist the implementation of sustainable procurement in public sector of Pakistan. We used Interpretive Structural Model to investigate and rank the interrelationships among different factors of sustainable procurement. With the help of literature and Likert scale instrument, we found twelve key barriers that resist sustainable procurement implementation. We also examined tender documents of 75 different public sector universities of Pakistan but found absence of sustainability element in the documents. External factors namely government legislation and stakeholders' pressure are found most critical barriers as compared to inter organizational factors. The study is also important to highlight the hurdles in the way of sustainable development. First, the government must introduce rules and regulations to implement the sustainable procurement. Stakeholders and donors must put pressure on organizations for adopting sustainable procurement. Sustainability education should be made mandatory part of curriculum and employees should be given regular training on sustainability. Further, public procurement policies at government and institutional levels are required to be revisited towards a circular economy.  相似文献   
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This study proposes a hybrid information approach to predict corporate credit risk. In contrast to the previous literature that debates which credit risk model is the best, we pool information from a diverse set of structural and reduced‐form models to produce a model combination based on credit risk prediction. Compared with each single model, the pooled strategies yield consistently lower average risk prediction errors over time. We also find that while the reduced‐form models contribute more in the pooled strategies for speculative‐grade names and longer maturities, the structural models have higher weights for shorter maturities and investment grade names.  相似文献   
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Construction kits have played a significant part in nurturing the growth and development of the minds and manipulation-based skills of children (and adults) in formal and non-formal education settings. These kits have origins rooted in the representation of the built world and now have a diversity of form and function, including technical versions with moving parts. This article examines some of the historically based ideas that lie behind the role that kits may have in terms of physical modelling. The article traces the transformation of kits from simple bricks and blocks into more complicated pieces for space-filling and achieving the transfer of forces and motion. This transformation occurred during the Victorian era when the influence of the ideas of educationalists and, perhaps rather strangely, exponents of early aviation, played major roles in determining the diversity of forms of construction kit and modelled possibilities that are now to be seen in classrooms and homes. The article ends with a review of some of the lessons from the past and present that will need to be considered in relation to concrete modelling in schools for the future. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
8.
说明了均匀、轴对称、无源介质是一个K-辛空间上的Hamilton系统,Hamilton函数是系统的守恒量;数值计算辐射强度角分布的合理途径是将辐射迁移方程离散成以离散Hamilton函数为守恒量的有限维K-辛空间上的正则方程,并采用保离散Hamilton函数守恒的K-辛算法数值求解.  相似文献   
9.
试论新制度经济学与中国体制改革的契合   总被引:1,自引:0,他引:1  
中国正在经历一个制度变迁的时代。新制度经济学对中国体制改革实践有很强的解释力和指导性,它与马克思主义经济学在机理上的相通及其与中国的传统政治文化的契合促进了它在中国的进一步发展。中国正处于一个制度变迁的时代,新旧体制转轨使中国有了对新的经济制度变革理论的强烈需要。新制度经济学适应了这种需求,对中国体制改革实践有很强的解释力和指导性。新制度经济学与马克思主义政治经济学有相通之处,这有利于发展新制度经济学,也有利于中国经济理论的衔接和发展。中国的传统政治文化与新制度经济学理论的契合,既有利于新制度经济学的传播,也有利于中国体制改革的进一步发展。  相似文献   
10.
The Amazon is the largest tropical forest area on Earth, and has been undergoing rapid deforestation for the last four decades. In the Brazilian Amazon, large‐scale pasture for cattle ranching and soybean production are the main land uses, leading to a yearly deforestation rate of 0.5%. These conversions are mostly located in frontier areas distributed along the so‐called “arc of deforestation”. Within this large zone, various land use change processes are interacting through several modes of land valuation and organisation. From several case studies in the State of Pará (Brazil), the current project aims at analysing how landscape dynamics are related to infrastructure development, ecological conditions, zoning policies and to the evolution and the organisation of the production, consumption and marketing chains of livestock products. This paper presents the results for one test site, the region of São Félix do Xingú, South of Pará This region is the focus of land speculation, cattle expansion, and deforestation. Road construction, investments in electrical energy, financial credit for cattle, and the land reform policies have all fuelled this process. All these factors make this region one of the most dynamic agricultural frontiers in the Brazilian Amazon. The main objective of the paper is to improve our understanding of deforestation processes by crossing spatial analyses and 1ivestock economics.studies, and to characterise the role and impact of various natural and anthropic factors in the location and development of the main types of farmers, and their policy implications.  相似文献   
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