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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.
Upgrading in global value chains (GVCs) is an important path for developing countries to move along to capture higher benefits. Several qualitative studies of GVCs have identified two main upgrading types: economic (product, process, functional, and inter-sectoral) and social upgrading. The upgrading concept is widespread in productive sectors such as processed food, which has become a key export for developing countries. However, they have confronted multiple product standards required by global buyers. This study uses a case study of Thailand’s processed food exports (TPFEs). Although Thailand is a leading exporter of processed food, the country needs to upgrade in many areas related to production to meet global product standards and requirements. If Thailand fails to comply with global product standards, it will lose its export competitiveness. This study uses a gravity model to evaluate the impact of economic and social upgrading (EUP and SUP) on TPFEs. Our results show that upgrading types are significant in TPFEs, particularly for exports to developed countries. Process upgrading has a negative impact on TPFEs because of increased production costs to comply with product standards. However, process upgrading can lead to increased producers’ and exporters’ knowledge about how to comply with international standards. Consequently, process upgrading exhibits a lagged positive effect on TPFEs.  相似文献   
3.
Artificial intelligence (AI) has captured substantial interest from a wide array of marketing scholars in recent years. Our research contributes to this emerging domain by examining AI technologies in marketing via a global lens. Specifically, our lens focuses on three levels of analysis: country, company, and consumer. Our country-level analysis emphasizes the heterogeneity in economic inequality across countries due to the considerable economic resources necessary for AI adoption. Our company-level analysis focuses on glocalization because while the hardware that underlies these technologies may be global in nature, their application necessitates adaptation to local cultures. Our consumer-level analysis examines consumer ethics and privacy concerns, as AI technologies often collect, store and process a cornucopia of personal data across our globe. Through the prism of these three lenses, we focus on two important dimensions of AI technologies in marketing: (1) human–machine interaction and (2) automated analysis of text, audio, images, and video. We then explore the interaction between these two key dimensions of AI across our three-part global lens to develop a set of research questions for future marketing scholarship in this increasingly important domain.  相似文献   
4.
疫苗作为新冠疫情防控的最关键手段之一,已在各国抗疫中发挥积极影响。疫苗研发、生产、注射意愿以及全球分配的公平性与可及性等一系列问题日益受到世界关注。分析全球治理改革中,疫苗作为一种全球公共产品的创新治理问题,讨论疫苗产业发展特征与创新规律演化,剖析西方国家疫苗产业创新治理困境以及“竞争丛林”逻辑,阐释中国行动方案及对全球治理改革的贡献。最终提出疫苗产业创新治理机制对推动全球治理改革的政策含义。  相似文献   
5.
We test for the performance of a series of volatility forecasting models (GARCH 1,1; EGARCH 1,1; CGARCH) in the context of several indices from the two oldest cross-border exchanges (Euronext; OMX). Our findings overall indicate that the EGARCH (1,1) model outperforms the other two, both before and after the outbreak of the global financial crisis. Controlling for the presence of feedback traders, the accuracy of the EGARCH (1,1) model is not affected, something further confirmed for both the pre and post crisis periods. Overall, ARCH effects can be found in the Euronext and OMX indices, with our results further indicating the presence of significant positive feedback trading in several of our tests.  相似文献   
6.
A number of simulation studies claim to have solved the Feldstein–Horioka puzzle by demonstrating that a high time-series correlation between saving and investment naturally arises from business cycle shocks. This paper uses panel data of saving and investment controlled for business cycle shocks to empirically test the significance of cyclical shocks — productivity, fiscal and the terms of trade shocks — in explaining a high saving–investment correlation. The estimation results reveal that conventional aggregate shocks only partially explain the high saving–investment correlation. Moreover, country differences in the size of the GNP and the non-traded sector do not significantly affect the saving–investment correlation. The saving–investment correlation puzzle remains a puzzle after all.  相似文献   
7.
缪燕燕 《基建优化》2005,26(1):76-78
在报价低者为优的评标规则下,报价、中标可得利润与中标概率总是成反比,最优报价为中标可得利润与中标概率的乘积最大时所对应的报价。结合案例详细分析了只有一个具体竞争对手,有若干具体竞争对手,已知对手数目但不知具体对象,既不知对手数目也不知具体对象四种情况下的报价决策方法。  相似文献   
8.
武威市凉州区农业种植结构调整的双目标优化   总被引:7,自引:0,他引:7       下载免费PDF全文
该文分别从经济效益最大化和生态效益最大化的目标出发,以土地资源、农作物用水量、区域各类农作物需求量和农业生产直接投入为约束条件,基于线性规划方法建立武威市凉州区农业种植业结构优化的经济效益模型和生态效益模型,并对两个模型的优化结果进行对比分析,认为以草地生态农业为生产模式的生态效益模型是凉州区实现农业可持续发展较为理想的模型。  相似文献   
9.
涂立桥 《经济经纬》2008,(2):156-158
笔者基于世代交叠模型,假定政府执行赤字预算体制,在市场结清的均衡状态下得到了确定国债规模与私人资本规模之比值的解析式。通过模拟发现税率、基本财政支出率、产出关于私人资本的弹性等是决定该比值大小的主要因素。  相似文献   
10.
基于聚类分析电信运营企业仓库布局优化研究   总被引:1,自引:0,他引:1  
祝丽  汝宜红  罗平 《物流技术》2007,26(8):106-109
以某电信运营企业为例,在现场调研的基础上,分析了企业仓库布局的主要问题,应用聚类分析方法,提出了仓库布局优化方案,并进行了方案的综合评价.  相似文献   
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