Nonlinear optimal control of coupled time-delayed models of economic growth

Decisions in Economics and Finance - The article proposes a novel nonlinear optimal control method for the dynamics of coupled time-delayed models of economic growth. Distributed and interacting...     

单自由度车辆系统动力学方程的非线性分析

文章根据车辆悬挂系统,建立非线性弹簧与线性阻尼的单自由度系统模型,运用平均法求出系统的幅频响应函数,根据幅频响应曲线讨论了车体质量,激励幅值,阻尼系数,弹簧刚度对曲线的影响,所得结果为车辆悬挂系统参数的选取提供了依据。     

The dynamics of economic convergence: The role of alternative investment decisions

In this paper we evaluate how various investment decisions explain the macroeconomic dynamics of European transition countries. We introduce quality investment decisions into a model with other two standard investment margins assumed in the advanced trade literature, i.e., investment in new varieties and in export eligibility. We show that the standard investment margins are not sufficient to simultaneously match the dynamics in the macroeconomic variables, especially the export performance and the real exchange rate. In contrast, the extended model with quality investment provides reconciliation.     

The dynamics of structural change: a model of economic development and urbanization

A system model is constructed for stimulating the development dynamics of a class of developing countries. The interrelations among socio-economic variables, feedback relations and the recursive relationship of intertemporal solutions are emphasized. For some plausible values of parameters and initial conditions, the model generates results generally consistent with the experience of many developing economies. Emerging from the dynamics are rapid urbanization accompanied by little industrial growth, increasingly unbalanced spatial distribution of population, ever-worsening distribution of income, unemployment and under-employment in both rural and urban areas, and other familiar features of the developing world unexplained by comparative-static equilibrium models.     

Properties in science and their modelling

Properties in the usual sense are analyzed by means of the construction of an abstract property. Once constructed, the abstract property provides a useful tool for analyzing the nature of usual properties. This paper shows that such modelling allows to classify properties and to explicate their structure. Applications of this modelling to study of some classical and quantum physical quantities are also described.     

Rural-urban migration in economic development

Abstract. This paper provides a review of the theoretical literature on rural–urban migration in contemporary LDCs. The paper begins with a brief discussion of the Lewis model before going on to discuss the Todaro and the Harris–Todaro models and the large literature which these models have spawned. The question of job search in the context of migration and the role of family members in migration decisions are considered next. The paper then takes a closer look at the Informal sector and also sets out alternative migration functions to the ones usually employed in the literature. The paper concludes with a brief note on some of the important implications arising from our study.     

Welfare paradox in economic restructuring

It can be proved theoretically that, because of the previously existing price and structural distortion, a welfare paradox is possible in the former command economies during the transition period. This paradox refers to a situation in which a welfare gain is accompanied by a fall in the reported GNP figure.     

Discrete choice modelling in airline network management

The task of airline network management is to develop new flight schedule variants and evaluate them in terms of expected passenger demand and revenue. Given the industry's trend towards global cooperation, this is especially important when evaluating the potential synergies with alliance partners. From the econometric point of view, this task represents a discrete choice modelling problem in which one has to account for a large number of dependent alternatives. In this paper we discuss the applicability of recently proposed approaches and introduce a new multinomial probit specification designed for the airline network management task. The superior performance of the new model is demonstrated in a real‐world application using airline bookings data. Copyright © 2005 John Wiley & Sons, Ltd.     

图腾在现代汽车标志造型中的应用

现代汽车的标志是代表一个汽车企业、汽车文化和汽车产品的视觉符号,每一个成功的车标都承载着本企业的巨大信息,展示着家族辉煌的历史。许多品牌的车标是通过运用家族图腾的符号来设计,并透过图腾文化给大众传达标志的内在信息,体现了品牌的精神气质和理念识别,成就了独特的车系派别和品牌文化。文章从汽车的家族图腾为切入点,探讨如何运用图腾元素设计现代汽车的标志。     

新经济形势下的叉车市场

近5年是中国叉车行业发展最快的5年.这种快速增长的势头一直保持到2008年,突然被国际金融危机打断.紧接着,中国叉车的产销量和出口量都出现了大幅下滑.今年1～2月行业形势依然严峻,国内叉车销售同比出现了35%左右的的下滑.目前,降幅正逐步收窄,市场呈现出回暖态势.     

Recent developments in French economic planning

Conclusions French planning seems to have had a very real effect on the economy in its early years. Industrialists' expectations were raised and new ideas were disseminated in a subtle way, and not merely because people believed the numerical values of published forecasts. In the early 1960s the idea of a consensus was extended beyond the need for greater private investment and the plan became the focus for a national debate on priorities. This exercise was valid and effective in a period of fast and accelerating growth but later the authorities chose instead to impose their own priorities, which included turning away from planning at the industrial level. This was partly because the underlying techniques of traditional French planning were seriously flawed in an open economy, but it probably also represented ideological preferences. However the consultative mechanisms continued to exist through the 1970s, though largely restricted to the macro-economic sphere. The 7th Plan generated a serious and powerful debate about responses to the recession but this was ignored by the authorities. Somewhat surprisingly, the reduced circumstances of planning did not affect the respect for its institutions in the eyes of other social actors: unions and business.¹⁰ In calling for a restoration of planning, the Socialists were therefore responding to a real need in a society with very limited channels for dialogue between social partners who nevertheless were forced to confront one another in the macro-economic sphere. But at the time of writing it looks as if an opportunity has been lost to carry out a detailed multi-scenario reflection on medium term economic policy.