Remaining life estimation of used components in consumer products: Life cycle data analysis by Weibull and artificial neural networks

Environmental awareness and legislative pressures have made manufacturers responsible for the take-back and end-of-life treatment of their products. To competitively exploit these products, one option is to incorporate used components in “new” or remanufactured products. However, this option is partly limited by a firm's ability to assess the reliability of used components. A comprehensive two-step approach is proposed. The first stage phase statistically analyzes the behavior of components for reuse. A well-known reliability assessment method, the Weibull analysis, is applied to the time-to-failure data to assess the mean life of components. In the second phase, the degradation and condition monitoring data are analyzed by developing an artificial neural network (ANN) model. The advantages of this approach over traditional approaches employing multiple regression analysis are highlighted with empirical data from a consumer product. Finally, the Weibull analysis and the ANN model are then integrated to assess the remaining useful life of components for reuse. This is a critical advance in sustainable management of supply chains since it allows for a better understanding of not only service requirements of product, but the remaining life in a product and hence its suitability for reuse or remanufacture. Future work should assess: (1) reduction in downtime of process equipment through the implementation of this technique as a means to better manage preventative maintenance; (2) reduce field failure of remanufactured product; (3) selling-service strategy through implementation of the proposed methodology.     

The role of marketing in the introduction of technologically new products: the case of the electric car

The energy and environmental crises are important problems facing the United States today. With less than 6% of the world's population, the U.S. accounts for 47% of the world's automobiles and nearly 35% of the total energy demand. Automobiles consume nearly 14.5% of the total energy demand and are the major source of air pollution. Whiel there are many potential solutions for the energy and environmental crises, this paper specifically focuses on how the electric car can be a partial answer to the complex problem of personal transportation. The paper specifically discusses the role of marketing in bridging the gap between technology and the consumer. On the basis of an extensive exploratory study, the authors contend that there is sufficient interest among consumers for an economical, pollution-free, electric car. Understanding the consumer's need and developing a product that is feasible, considering existing technology, is the role that marketing must play.     

Designing a guideline-based utilization management program

Many public and private organizations are developing and publishing clinical guidelines to assist health care providers and patients in making appropriate medical decisions. Unless clinical guidelines are part of a well-designed managed care program, they have little effect on physician practice styles. This article explores integral components of an effective guideline-based utilization management program. Initial evaluation of this program suggests that, as part of a well-designed utilization management program, clinical guidelines can inform patients and physicians, and create appropriate incentives for effective health care delivery.     

Growth and equity effects of changing demographic structures in the Netherlands: simulations within a social accounting matrix

"This paper deals with the economic consequences of a changing demography in an industrialized country, namely the Netherlands. The analytical framework chosen is that of general equilibrium as statistically given by the social accounting matrix (SAM) in which we introduce households by size for the present economic demographic situation (1981) and for a future simulated situation (2010) featuring in particular a relative increase in one-person households (individualization). The income (output) multipliers of both SAMs show a positive growth bias towards three and more person households and towards mining, public utilities, trade and banking."     

The welfare effects of import “subquotas” on heterogeneous product categories

In spite of its importance to policy makers, surprisingly little attention has been paid to the welfare effects of one aspect of trade policy-how to implement an import quota that applies to a heterogeneous product category. The government can impose a simple quota that applies indiscriminately to all goods within the product category or it can divide the quota among them with subquotas. In this paper, we analyze the welfare effects of subquotas. Under certain simplifying assumptions we find that a system of subquotas nearly always exists that provides greater welfare than a simple quota for a large country that retains quota rights or for a large or small country that gives quota rights away to foreigners. However, subquotas cannot increase the welfare of a small country that retains quota rights. The difference lies in the effect of imports on the home country's terms of trade.The views expressed in this paper are those of the authors and do not necessarily reflect the opinion of the US International Trade Commission. The authors are grateful for helpful comments on an earlier draft by anonymous referees.     

Intention and Stochastic Outcomes: An Experimental study

Do people care about intentions – even when good intentions do not produce good results? In our experiments we find that rates of punishment and reward react strongly to intentions (the wage a firm decides to pay) and more modestly to distributional outcomes (the higher or lower wage actually received including the stochastic component). For example, workers who end up receiving medium wages respond much more positively when this resulted from the firm offering a high wage but bad luck lowered the worker's pay than when this resulted from the firm offering a low wage and good luck raised the pay.     

Regional, national, and spatially explicit scenarios of demographic and economic change based on SRES

We report here spatially explicit scenario interpretations for population and economic activity (GDP) for the time period 1990 to 2100 based on three scenarios (A2, B1, and B2) from the IPCC Special Report on Emissions Scenarios (SRES). At the highest degree of spatial detail, the scenario indicators are calculated at a 0.5 by 0.5 degree resolution. All three scenarios follow the qualitative scenario characteristics, as outlined in the original SRES scenarios. Two scenarios (B1 and B2) also follow (with minor adjustments due to scenario improvements) the original SRES quantifications at the level of 4 and 11 world regions respectively. The quantification of the original SRES A2 scenario has been revised to reflect recent changing perceptions on the demographic outlook of world population growth. In this revised “high population growth” scenario, A2r world population reaches some 12 billion by 2100 (as opposed to some 15 billion in the original SRES A2 scenario) and is characterized by a “delayed fertility transition” that is also mirrored in a delayed (economic) development catch-up, resulting in an initially stagnating and subsequently only very slow reduction in income disparities. The spatially explicit scenario interpretation proceeds via two steps. Through a combination of decomposition and optimization methods, world regional scenario results are first disaggregated to the level of 185 countries. In a subsequent second step, national results are further disaggregated to a grid cell level, taking urbanization and regional (rural–urban) income disparities explicitly into account. A distinguishing feature of the spatially explicit scenario results reported here is that both methodologies, as well as numerical assumptions underlying the “downscaling” exercise, are scenario-dependent, leading to distinctly different spatial patterns of population and economic activities across the three scenarios examined.     

Welfare effects of 1992: A general equilibrium assessment for EC and EFTA countries

In this paper production, trade and welfare effects of European integration are discussed, with particular emphasis on the effects for the EC and EFTA. Insights from previous partial and general equilibrium analyses of the internal market are reviewed, and new model simulations are presented. In addition to the standard experiments of 1992 — as reduced trade costs and as full market integration — for the EC alone, and for the European Economic Area (EEA), an intermediate case, with full integration in the EC but only lower trade costs between the EC and EFTA, is analysed. All cases show that EFTA will benefit significantly from freer trade and closer integration with the EC. With regard to non-European regions, the simulations of European integration show some degree of trade diversion, but stylized model experiments indicate that a successful outcome of the Uruguay-round may more than offset the trade-diverting effects of 1992.     

Some comparative-statics results for nonlinear input-output models of a multisectored economy,and related results for nonlinear price-demand relations

For a nonlinear version of the linear input-output model of Leontief, we consider the effect, on the vector x of total gross outputs, of changes in the components of the final-demand vector c. For example, it is shown that, for a certain important class of models, the “large-change elasticity” of any component of x, with respect to any component of c, is less than or equal to unity. Some similar results are proved concerning properties of nonlinear price-demand relations for the case in which all goods are weak gross substitutes. Unlike earlier work in this general area, we do not introduce hypotheses concerning the indecomposability or homogeneity of certain mappings. For that reason, the results are valid for the price-demand relation for a single firm, or for any collection of firms.