A Discontinuity Model of Technological Change: Catastrophe Theory and Network Structure

Discontinuities as a crucial aspect of economic systems have been discussed both verbally—particularly in institutionality theory—and formally, chiefly using catastrophe theory. Catastrophe theory has, however, been criticized heavily for lacking micro-foundations and has mainly fallen out of use in economics and social sciences. The present paper proposes a simple catastrophe theory model of technological change with network externalities and reevaluates the value of such a model by adding an agent-based micro layer. To this end an agent-based variant of the model is proposed and investigated specifically with regard to the network structure among the agents. While the macro level of the model produces a classical cusp catastrophe—a result that is preserved in the agent-based form—it is found that the behavior of the model changes locally depending on the network structure, especially if networks with features that resemble social networks (low diameter, high clustering, power law distributed node degree) are considered. While the present work investigates merely an aspect out of a large possibility space, it encourages further research using agent-based catastrophe theory models especially of economic aspects to which catastrophe theory has previously successfully been applied; aspects such as technological and institutional change, economic crises, or industry structure.     

Model theory approach to transaction processing system development

This paper presents a new approach, model theory approach, to small and medium scale transaction processing system (TPS) development. A TPS of this paper is an information system designed to process day-to-day business event data at operational level of an organization. The paper is not concerned with data base construction but with transaction processing.

The model theory approach is not a software engineering approach but a systems theory approach. In the approach a model of the target system, which is called a user model, is constructed in set theory using a formal system structure of a TPS. The user model is, then, compiled into an extended Prolog (extProlog) model. The extProlog is an extension of Prolog to meet requirements for management information system development. On compilation a standardized user interface (UI) called internal UI is attached. The extProlog model with the internal UI is, then, executed under control of another standardized UI called an external UI. Implementation is an integral part of the approach. Because the UIs are designed for the formalized (abstract) structure of a TPS, they can be standardized and are provided as black box components to system development. Because a systems developer is required to only build a user model in set theory based on a model theoretic structure in the approach, it is called a model theory approach. Advantages of this approach are that it provides a theoretical structure to information systems development so that systems development can be made an engineering discipline, and facilitates rapid systems development.     

Risk-sensitive ICAPM with application to fixed-income management

This paper presents an application of risk-sensitive control theory in financial decision making. A variation of Merton's continuous-time intertemporal capital asset pricing model is developed where the infinite horizon objective is to maximize the portfolio's risk adjusted growth rate. The resulting model is tractable and thus provides economic insight about optimal trading strategies as well as the fact that the strategy of 100% cash is not necessarily the least risky one. For fixed-income applications we utilize the concept of rolling-horizon bonds, which are stochastic process models of certain mutual funds of zero coupon bonds. We show by numerical example that the optimal proportion of one's wealth to hold in an asset is given by a simple affine function of economic factors such as interest rates of various maturities.     

多机服务器任务调度的经济学方法

本文针对多机服务器提出了一种任务调度的经济学方法 :以一般均衡理论为基础 ,依靠价格机制实现资源的优化分配 ;讨论了多机服务器的系统模型、任务的聚类和效用函数、经济学模型及均衡状态的最优性 ;最后通过模拟实验验证了经济学方法的有效性     

多机服务器任务调度的经济学方法q

本文针对多机服务器提出了一种任务调度的经济学方法以一般均衡理论为基础,依靠价格机制实现资源的优化分配;讨论了多机服务器的系统模型、任务的聚类和效用函数、经济学模型及均衡状态的最优性;最后通过模拟实验验证了经济学方法的有效性。     

技术创新下战略性新兴产业升级的金融支持研究

金融是现代经济的核心,是引导经济资源配置的重要动力机制。“十二五”期间,战略性新兴产业的培育、发展与升级问题已成为我国经济社会发展的重要战略目标,而金融体系在战略性新兴产业的培育、发展与升级过程中具有核心的支持作用。文章以分析战略性新兴产业的业态演进过程为切入点,基于技术创新视角构建了战略性新兴产业升级的金融支持体系,并进一步设计了基于间接金融和直接金融路径的战略性新兴产业升级的金融支持政策。本研究将为我国制定科学高效的国家产业发展政策与金融财政政策,提供重要的理论指导与决策参考,具有非常重要的理论与现实意义。     

Automatic linear causal relationship identification for financial factor modeling

Given a comprehensive set of financial factors, we use linear non-Gaussian SEM to automatically identify the causal relationships buried in the factor set. The causal structure is allowed to have cyclic edges, explicitly accommodating ‘mutual causality’ which is well acknowledged but rarely modeled in standard economic theory. The method takes advantage of both artificial intelligence and economic related techniques, and identifies one stable model from several distribution-equivalent equilibrium models for each dataset. Empirical studies on 15 financial factors reveal some interesting findings, especially for the risk-return relationship modeling and capital structure determinants discovery.     

A fuzzy control system with application to production planning problems

A considerable part of the literature on fuzzy sets is devoted to the field of fuzzy control system. In this paper, an alternative control system is introduced to describe a dynamic system with fuzzy white noise. In order to find optimal ways to control such a system, fuzzy optimal control theory is further developed. Specifically, a linear quadratic model is formulated and solved as a fuzzy optimal control problem. The formulation and solution of this model provide an economic interpretation of a production planning model both in the finite horizon and in the infinite horizon.     

国民经济系统消费跟踪控制理论

本文提出一种新的经济系统思想——国民经济系统消费跟踪控制理论。这一理论是建立在现代控制理论、投入产出技木和社会主义经济原理基础之上的。笔者试图据此解决宏观经济计划中最基本的问题,诸如如何安排消费和投资的比例等。对该理论以及模型的应用,本文进行了详细的讨论并举例作了说明。     

灰色系统理论预测算法研究及其在农村经济分析中的应用

三农问题是全面建设小康社会的关键问题.为确保农村经济的稳定发展,对农村经济发展的科学预测就显得尤为重要.运用灰色系统理论对农村经济预测问题进行了研究,建立了灰色数学模型,讨论了模型的建立、参数求解、模型的检验等.最后分析了农村经济数据的特点,并运用matlab GUI完成了灰色预测算法的实现.     

Economic model predictive control of nonlinear singularly perturbed systems

We focus on the development of a Lyapunov-based economic model predictive control (LEMPC) method for nonlinear singularly perturbed systems in standard form arising naturally in the modeling of two-time-scale chemical processes. A composite control structure is proposed in which, a “fast” Lyapunov-based model predictive controller (LMPC) using a quadratic cost function which penalizes the deviation of the fast states from their equilibrium slow manifold and the corresponding manipulated inputs, is used to stabilize the fast dynamics while a two-mode “slow” LEMPC design is used on the slow subsystem that addresses economic considerations as well as desired closed-loop stability properties by utilizing an economic (typically non-quadratic) cost function in its formulation and possibly dictating a time-varying process operation. Through a multirate measurement sampling scheme, fast sampling of the fast state variables is used in the fast LMPC while slow-sampling of the slow state variables is used in the slow LEMPC. Appropriate stabilizability assumptions are made and suitable constraints are imposed on the proposed control scheme to guarantee the closed-loop stability and singular perturbation theory is used to analyze the closed-loop system. The proposed control method is demonstrated through a nonlinear chemical process example.     

An application of interpretive structural modelling to analyse preference structure in multiobjective dynamic environmental-economic systems†

This paper applies ISM (interpretive structural modelling) to analyse preference structure in a multiobjective problem of a dynamic environmental-economic model, and terms this method IPSM (interpretive preference structural modelling). Multi-objectives in the model include minimizing social cost of pollution, and maximizing total consumption in a planning interval. IPSM analyses decision-maker's preference relations (mental model) among many Pareto-optimal solutions of the multiobjective systems under the interactive cooperation between the decision-maker and the model-builder, and extracts the decision-maker's preference structure as a hierarchical directed graph, where the vertices of the graph correspond to the Pareto-optimal solutions and the directed edges correspond to the preference relations. An interesting economic interpretation for a preferred solution is discussed in terms of the economic interpretation of the discrete minimum principle.     

An approach to on-line power dispatch with ambient air pollution constraints

An on-line optimal environmental/economic dispatch methodology for electric power generation is developed in this paper. Aside from the conventional economic dispatch, constraints on air quality (such as those specified by the U.S. Environmental Protection Agency) are added to the minimum fuel cost problem. Using the integrated Gaussian puff model based on the statistical turbulent theory, rapid dynamic features of pollutant dispersion and its forecast surrounding the plants are emphasized. By applying a convex programming algorithm repeatedly, a set of marginal environmental imposts for the power plants at different times are obtained. Such imposts are incorporated with the fuel cost in the ordinary short-term economic dispatching program to indirectly account for the environmental impact of power generation on the quality of the ambient air. The approach is specifically taken to have little modification for existing economic dispatch programs and be implemented for real power networks. The proposed approach has been simulated in a power system with three plants and three monitoring points.     

Optimal estimation control strategies for dynamic economic models with applications to environmental modelling

As controlled experimentation becomes more common in economics, it behoves economists to pay more attention to the peculiarities of economic experimentation. In particular, while most classical experimentation is essentially atemporal, economic experiments occur over a period of time, because individual economic units must adjust their activities to react to the incentive structure of the experiments. In this paper the choice of control strategies to improve estimation of the parameters in dynamic economic models with time-varying parameters is considered. Since restrictions of coefficients implied by the model structure cause the parameters also to appear in the solution of the estimation control problem, a sequential procedure immediately suggests itself. The combination of sequential estimation and design control strategies is shown to feature a marked improvement in the behavior of estimates over the nonsequential formulation. The maximum accuracy control problem considered in this paper can also be treated as an initial phase of a stochastic control problem. This will avoid solution to a difficult dual control problem. Finally, examples are presented illustrating the improvement in estimation accuracy that can be obtained.     

Constructing structural VAR models with conditional independence graphs

In this paper graphical modelling is used to select a sparse structure for a multivariate time series model of New Zealand interest rates. In particular, we consider a recursive structural vector autoregressions that can subsequently be described parsimoniously by a directed acyclic graph, which could be given a causal interpretation. A comparison between competing models is then made by considering likelihood and economic theory.     

Stochastic contraction-based observer and controller design algorithm with application to a flight vehicle

This paper focuses on a stochastic version of contraction theory to construct observer-controller structure for a flight dynamic system with noisy velocity measurement. A nonlinear stochastic observer is designed to estimate the pitch rate, the pitch angle, and the velocity of an aircraft example model using stochastic contraction theory. Estimated states are used to compute feedback control for solving a tracking problem. The structure and gain selection of the observer is carried out using Itô's stochastic differential equations and the contraction theory. The contraction property of integrated observer-controller structure is derived to ensure the exponential convergence of the trajectories of closed-loop nonlinear system. The upper bound of the state estimation error is explicitly derived and the efficacy of the proposed observer-controller structure has been shown through the numerical simulations.     

Economic plant-wide control design with backoff estimations using internal model control

Economic optimal operation typically involves operating as close as possible to the active constraints. However, in the presence of disturbances it is necessary to back-off from the constraints in order to avoid violating them. The backoff approach aims at selecting the control structure that minimizes the economic loss associated with the required constraint backoffs. This paper revisits the backoff approach and proposes a framework for estimating the constraint backoffs based on well-known elements of internal model control (IMC) theory, such as an automatic procedure for tuning the IMC low-pass filters, a stability condition, and an uncertainty representation based on diagonal input multiplicative uncertainty. Since the constraint backoffs are estimated using a linear dynamic model, the inclusion of input multiplicative uncertainty allows introducing conservatism in the estimation of the backoffs, which is required in order to avoid constraint violations. A forced-circulation evaporator benchmark problem is used to illustrate the approach.     

Exploring information technology outsourcing relationships: theory and practice

A growing concern among the organisations who are actively involved in Information Technology outsourcing is post-contract management and the ensuing development of what many practitioners and scholars have coined the ‘outsourcing partnership’. This paper integrates theoretical concepts from organisation theory, social exchange theory, and relational contract theory with existing research on IT outsourcing, to develop a conceptual model for understanding the relationship. In particular, we conceptually elaborate and then address the relationship's properties — identified as interactions, contract, context, structure, and behavioural dimensions. Preliminary exploratory research into relationship practice in twelve organisations involved in outsourcing presents some interesting findings that advance the thinking about the outsourcing relationship. We found the conceptual model useful in elucidating important relationship management areas, highlighting not only the outsourcing relationship's contractual, social, and economic characteristics, but also many additional elements found to have relevance in practice.     

Optimal control of economic growth with application to Korean economy

This paper is concerned with the application of optimal control theory to the dual growth of the Korean economy. A closed two sector economic growth model is formulated by dividing the economy into agriculture and non-agriculture in order to represent the transitional phenomena between the two sectors. Taking capital and saving as state and control variables, respectively, the model governing the economic growth becomes a non-linear simultaneous differential equations with coupling terms of state and control variables. Assuming the Cobb-Douglas production function and the exponential form of the social welfare function, the necessary and sufficient conditions of the optimal control have been derived for the case of finite planning horizon by using the Pontryagin's maximum principle. Since deriving the optimal trajectories of state and control variables analytically is impossible, a numerical procedure based on the variation of extremals is used to obtain the optimal paths of the aggregate investment and consumption of the Korean economy.     

基于 EKC 理论与 LMDI 因素分解的经济增长与碳排放关系研究

本文基于EKC理论对云南省经济增长与碳排放之间的关系进行验证,结果表明二者之间不存在倒U型曲线,而是呈线性关系,并且存在长期的协整关系。采用LMDI分解方法对云南省人均碳排放进行因素分解,结果表明经济发展是拉动人均碳排放增长的主要因素,能源效率和能源结构是抑制碳排放增长的因素。最后,在上述分析的基础上,提出了几点建议。