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21.
综述了近年来生物质可降解聚氨酯材料的种类,主要包括纤维素改性聚氨酯、低聚糖改性聚氨酯、木质素改性聚氨酯、单宁改性聚氨酯、树皮改性聚氨酯、淀粉改性聚氨酯及其它物质改性聚氨酯。 相似文献
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本文阐明了蛇口工业区目前所处的内、外环境,运用差别优势理论对此进行系统分析,拟定了“投资转向。项目为主;引进重点,资金密集:依托招商,港航率先;内外布点,走向世界”的发展战略。作者认为,这一战略的实施,有助于蛇口从“引进来”的战略重点向“走出去”的战略重点转移。文中对战略推进的措施提出了具体的设想,描绘了战略的近期目标和详细的动态战略图,并对战略制定的方法和理论作了新的探索。 相似文献
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Growth rates of part-through and through fatigue cracks have been measured for two magnesium alloys — MA12 and IMV6 — and the micromechanisms of fatigue fracture were studied at all stages of growth. Conclusions about the peculiarities of the kinetics and micromechanisms of part-through and through crack growth, depending on the applied stress amplitudes and alloy structure, are made from a comparison of the results obtained. 相似文献
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We develop an algorithm to compute asset allocations for Kahneman and Tversky’s (Econometrica, 47(2), 263–291, 1979) prospect theory. An application to benchmark data as in Fama and French (Journal of Financial Economics, 47(2), 427–465, 1992) shows that the equity premium puzzle is resolved for parameter values similar to those found in the laboratory
experiments of Kahneman and Tversky (Econometrica, 47(2), 263–291, 1979). While previous studies like Benartzi and Thaler (The Quarterly Journal of Economics, 110(1), 73–92, 1995), Barberis, Huang and Santos (The Quarterly Journal of Economics, 116(1), 1–53, 2001), and Grüne and Semmler (Asset prices and loss aversion, Germany, Mimeo Bielefeld University, 2005) focussed on dynamic aspects of asset pricing but only used loss aversion to explain
the equity premium puzzle our paper explains the unconditional moments of asset pricing by a static two-period optimization
problem. However, we incorporate asymmetric risk aversion. Our approach allows reducing the degree of loss aversion from 2.353
to 2.25, which is the value found by Tversky and Kahneman (Journal of Risk and Uncertainty, 5, 297–323, 1992) while increasing the risk aversion from 1 to 0.894, which is a slightly higher value than the 0.88 found
by Tversky and Kahneman (Journal of Risk and Uncertainty, 5, 297–323, 1992). The equivalence of these parameter settings is robust to incorporating the size and the value portfolios
of Fama and French (Journal of Finance, 47(2), 427–465, 1992). However, the optimal prospect theory portfolios found on this larger set of assets differ drastically
from the optimal mean-variance portfolio. 相似文献
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In this paper, a method based on prospect theory is proposed to solve the multiple attribute decision making (MADM) problem considering aspiration-levels of attributes, where attribute values and aspiration-levels are represented in two different formats: crisp numbers and interval numbers. According to the idea of prospect theory, aspiration-levels are firstly regarded as the reference points, and the four possible types for comparing an attribute value with an aspiration-level are described. Then, for all possible cases of the four types, the calculation formulae of gains and losses of alternatives concerning attributes are given. By calculating gain and loss of each alternative, a gain matrix and a loss matrix are constructed, respectively. Further, using the value function proposed in prospect theory and the simple additive weighting method, the overall prospect value of each alternative is calculated. Based on the obtained overall prospect values, a ranking of alternatives can be determined. Finally, a numerical example is used to illustrate the use of the proposed method. 相似文献