生命周期评价方法及其应用

介绍了生命周期评价的目的、意义和基本方法，并运用该方法对燃煤发电、废纸造纸、废旧塑料气化发电等几种不同工业过程的环境影响进行了分析。     

西汉初期“与民休息”政策述论

西汉初期是我国农业经济迅速恢复并达到空前繁荣的时期,这与西汉初期统治集团采取了比较符合实际的"与民休息"的经济政策紧密相关。其时代背景主要是鉴于秦朝实行严刑峻法、横征暴敛政策而亡的历史教训,以及汉初经济崩溃、民生凋敝的实际状况。"与民休息"政策内容丰富,主要包括调整土地关系、赋予军功贵族免役特权、免部分官私奴婢为庶人、减免田税口算徭戍、崇尚节俭和轻刑慎罚等六个方面。"与民休息"的经济政策,将为我们今天解决"三农"问题,发展农业经济,建设社会主义新农村提供有益的借鉴。     

Replacement Investment: Optimal Economic Life Under Uncertainty

Replacement investment is essentially a regenerative optimal stopping problem; that is, the key decision concerns when to terminate the life of existing plant – and hence when to start over again. This paper examines this optimisation problem within a continuous time framework and studies the qualitative and quantitative impact of uncertainty on the timing of new investment (and the criteria that should be used for terminating the life of existing plant).     

Consumption and stock markets in Asian economies

This paper investigates the causal links between stock market performance and consumption for five Asian economies by applying the bound tests of Pesaran et al. and lag augmented VAR of Toda and Yamamoto . We find two‐way causal relationships between stock market performance and consumption in the cases of Hong Kong and Taiwan in the long run. The existence of such two‐way causal links indicates that stock market performance and consumption mutually affect each other, implying that the previous studies may have overestimated the wealth effect of the stock markets without taking account of the reverse causation from consumption to the stock markets. The short‐run effect of the stock market on consumption is more visible than the long‐run effect in most of the sample economies, suggesting that changes in consumption directly reflect stock market fluctuations.     

Multiple generation product life cycle predictions using a novel two-stage fuzzy piecewise regression analysis method

Product life cycle (PLC) prediction plays a crucial role in strategic planning and policy definition for high-technology products. Forecast methodologies which can predict PLCs accurately can help to achieve successful strategic decision-making, forecasting, and foresight activities in high-technology firms, research institutes, governments, and universities. Over the past few decades, even though analytic framework strategies have been proposed for production, marketing, R&D (research and development), and finance, aiming at each stage of PLCs, forecast methodologies with which to predict PLCs are few. The purpose of this research is to develop a novel forecast methodology to allow for predictions of product life time (PLT) and the annual shipment of products during the entire PLC of multiple generation products. A novel two-stage fuzzy piecewise regression analysis method is proposed in this paper. In the first stage, the product life-time of the specific generation to be analyzed will be predicted by the fuzzy piecewise regression line that is derived based upon the product life-time of earlier generations. In the second stage of the forecast methodology, the annual shipment of products of the specified generation will be predicted by deriving annual fuzzy regression lines for each generation, based upon the historical data on the earlier generations' products. An empirical study predicting the life-time and the annual shipment of the 16 Mb (Mega bit) DRAM (Dynamic Random Access Memory) PLC is illustrated to validate the analytical process. The results demonstrate that two-stage fuzzy piecewise regression analysis can predict multiple generation PLT and PLC precisely, thereby serving as a foundation for future strategic planning, policy definitions and foresights.     

Hypothesis tests using data envelopment analysis

A substantial body of recent work has opened the way to exploring the statistical properties of DEA estimators of production frontiers and related efficiency measures. The purpose of this paper is to survey several possibilities that have been pursued, and to present them in a unified framework. These include the development of statistics to test hypotheses about the characteristics of the production frontier, such as returns to scale, input substitutability, and model specification, and also about variation in efficiencies relative to the production frontier.     

The Nested PIGLOG Model: An Application to U.S. Food Demand

A new demand system is introduced, the Nested PIGLOG model, nesting thirteen other demand systems including five that are also new. This new model and its nested special cases are applied to models of U.S. food demand that include food-at-home (FAH), food-away-from-home (FAFH), and alcoholic beverages. Although nested tests and out-of-sample forecasting performance favor generalizing models to a certain degree, statistically insignificant improvements to in-sample-fit and even poorer out-of-sample forecast accuracy undermine further generalizations. Based on a subset of preferred models, FAFH is found to be price and income elastic compared to FAH which is price and income inelastic.     

Learning across the life cycle: Experimentation and performance among the hollywood studio heads

Guided by notions from the literature on organizational learning, this paper investigates how product line experimentation and organizational performance change across the careers of top managers. Its subjects are the studio heads who ran all the major Hollywood film studios from 1936 to 1965. The study found first, that product line experimentation declines over the course of executive tenures; second, that there is an inverse U‐shaped relationship between top executive tenure and an organization's financial performance; and third, that product line experimentation is more likely to benefit financial performance late in top executives' tenures. These findings are consistent with a three‐stage ‘executive life cycle’. During the early years of their tenures, top managers experiment intensively with their product lines to learn about their business; later on their accumulated knowledge allows them to reduce experimentation and increase performance; finally, in their last years, executives reduce experimentation still further, and performance declines. Copyright © 2001 John Wiley & Sons, Ltd.     

Progressive stress accelerated life tests under finite mixture models

In this paper, progressive stress accelerated life tests are considered when the lifetime of a product under use condition follows a finite mixture of distributions. The experiment is performed when each of the components in the mixture follows a general class of distributions which includes, among others, the Weibull, compound Weibull, power function, Gompertz and compound Gompertz distributions. It is assumed that the scale parameter of each component satisfies the inverse power low, the progressive stress is directly proportional to time and the cumulative exposure model for the effect of changing stress holds. Based on type-I censoring, the maximum likelihood estimates (MLEs) of the parameters under consideration are obtained. A special attention is paid to a mixture of two Rayleigh components. Simulation results are carried out to study the precision of the MLEs and to obtain confidence intervals for the parameters involved.     

晚清民初上海文人的经济生活与身份转型——以王韬、包天笑为例

近代上海城市的发展，把一批传统士人卷了进来，中国文人由此开始走出延续千百年的仕途经济，走向近代城市的分工体系和独立职业空间。作为晚清上海初始城市化的亲历者，王韬在文化心理和经济生活两方面，经历了一场由“士人”转向城市职业者的艰难蜕变。而生活于清末民初上海的包天笑，则以明确的职业归属感，取代了传统士人的仕宦情结，中国文人至此初步完成了由传统政教依附者向近代独立文化人的转型。