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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.
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   
3.
Hybrid governance forms that seek to meld the virtues of both market control and traditional hierarchical control are alluring. Comparatively little research, outside of the M-form literature, has examined internal hybrids - hierarchical forms infused with elements of market control. This paper contends that common change initiatives, such as TQM, re-engineering, autonomous work teams, and group-based rewards, are appropriately viewed as attempts to craft internal hybrids by selectively infusing elements of market control within hierarchy. However, these change initiatives are often implemented in isolation and, as a consequence, violate patterns of complementarity that sustain traditional hierarchy or support the stable infusion of market control.The paper argues that these violations of complementarity often spiral hierarchies toward fundamental transformation. The clear trajectory of these transformations is to quite radically disaggregated organizations structured around teams. The paper presents both theory and evidence supporting the existence of complementarities among these common change initiatives.  相似文献   
4.
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   
5.
本文综述了混合拉曼/掺饵光纤放大器(HFA)的工作原理,结构和特点,介绍了4类HFA基本结构及其实验结果,并通过介绍近年来各类HFA在密集波分复用(DWDM)系统中的应用表明了HFA在带宽,增益和噪声特性方面的优点。  相似文献   
6.
The paper introduces the highly problematic nature of modelling in design and technology education and examines the relationship between cognitive and concrete modelling. Its aim is to gain insight into what learners do, rather than what others say they ought to do in their learning activities. The variety of purposes that educators have for learners’ modelling are discussed through examining the contested curriculum justification for design and technology education itself. The paper proposes that learners’ modelling cannot be extracted from the social milieu in which they act and it provides some insights of these social influences through the analysis of two case studies. Their settings are a girls’ secondary school and a college of higher education. Each case study is presented independently but organised with a common format to consider a) the impact of assessment on learning intentions and outcomes; b) cultural influences on learning and modelling; c) social influences on learning and modelling. A discussion of the emergent themes considers implications for teachers. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
7.
Hybrid organisations present important theoretical and managerial opportunities. We examine a large Finnish multichain retail organisation in order to identify and understand the challenges of hybrids in a retailing context. We are especially interested in how these complex firms try to maintain a balance between the centralised corporate control and the local autonomy and initiative of their retailers. The governance forms and processes identified in the case organisation are discussed with the help of a proposed conceptual framework. We believe that the identified governance problems and practices in the three different retail chains and especially our recommendations will facilitate the understanding of retail hybrid organisations and the management of hybrids in general.  相似文献   
8.
Faced with a record level of unemployment, the present debate in Germany is to extend the weekly hours of work. In this paper the employment effects of an economy-wide increase in weekly hours are quantified on the basis of a computable general equilibrium model for different specifications of the wage setting rule and the use of additional policy-induced public income. The simulation results back the argument of the opponents of longer working time that not more jobs will be created. However, when the higher tax revenues from GDP growth are used to reduce social security contributions, then the claim of the proponents that more jobs will be created can be supported.  相似文献   
9.
This paper provides a theoretically informed analysis of how institutional pluralism unfolds in hybrid organizations through practices. Building on Quattrone's (2015) procedural model, the paper studies institutional plurality in the case of an Italian cooperative bank that has experienced enduring success. By reversing the usual approach to logic, defined as a stable set of beliefs, this paper shows that this hybrid organization uses a recursive system of practices in search of social order. This hybrid organization interrogates its organizational imperatives and defines adequate ways to achieve them. This paper then observes that this system of practices is permeable to external pressures, i.e., inspections by the central bank, a reform of cooperative banks, political pressure for mergers and acquisitions, and Italy's sovereign debt crisis. While such an organization appears to be ongoingly accountable to its multiple stakeholders, external pressures undermine its community accountability system and push this hybrid organization towards compliance accountability. Based on our findings, this paper develops a process model for hybrid organizations to navigate institutional plurality and to explain the potential limitations of the accountability system.  相似文献   
10.
In this paper we introduce a new econometricapproach to analyzing recreational site choicedata, the Dirichlet multinomial model. Thismodel, which nests the standard conditionalmultinomial logit model, can accommodateover-dispersed data and may provide moreefficient estimators of coefficients andconsequent welfare measures than the standardconditional logit model, which is so widelyused in the Random Utility Model approach torecreation demand. We illustrate thisDirichlet approach using a data set of rockclimbers in Scotland, and study the impacts onper-trip consumers surplus of alternativemanagement strategies for popular rock climbingsites. Results show that the Dirichletmultinomial approach produces coefficient andwelfare estimates having smaller samplingvariability in this case. We also compareclassical welfare measures with their posteriorequivalents, which allow for welfare changes tobe dis-aggregated.  相似文献   
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