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ABSTRACT We develop a generalized Harrod-Domar type of model for optimal regional growth which allows determination of the optimal allocation of regional public investments and which considers multiple growth objectives, as well as both normal and singular fiscal instruments. This general model is shown to include most of the previous optimal regional growth models as special cases. Necessary conditions for some special cases of the general model are analyzed in detail, and decision rules associated with derived optimal regional growth policies are articulated. These special cases verify that singular controls do exist in certain instances, and that they must be considered for the complete specification of optimal regional growth policies; this is significant because singular controls have not been previously analyzed in the literature. We conclude the paper with a discussion of sufficiency conditions for optimal regional growth models which is more general than that given by previous authors. 相似文献
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Stephen L White 《政策研究杂志》1987,15(3):375-393
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The advent of new techniques of dental ageing has permitted inferences about the age-structures of ancient animal populations on the basis of faunal remains. Unfortunately, inference from archaeological populations of faunal elements to the age-structure of ancient herds is fraught with both sampling problems and logical difficulties. The relationship between a living herd—a dynamic system characterized by growth—and a static archaeological population is more complex than that assumed by current models based on kill-off patterns and survivorship curves. Using a computer simulation, these logical relationships are explored, and the effects of herd growth on the composition of live and death populations are evaluated. By employing the simulation within a deductive framework, constrained by ethnographically derived criteria for reproduction, mortality, and economic viability in the Near East, it is possible to determine whether certain archaeological kill-off patterns could represent viable herding systems. Examples were found to vary widely in terms of both demographic plausibility and economic viability. Some implications for the possible course of ova-caprine domestication in the Near East are discussed. 相似文献
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Sarah A. Bendall 《Gender & history》2023,35(1):42-67
This article examines the visual and material culture of sixteenth-century elite ceremonial armours and the paradoxes inherent in using images of women to decorate them between 1525 and 1550. It argues that foreign invading forces and their allies exploited or inverted traditional gender binaries associated with the classical and humanist iconography of the Italian Renaissance, particularly its female allegorical forms, to visually signify power relationships between combatants during the Italian Wars. Rather than simply embodying masculinity, elaborate ceremonial armours with images of women are revealing of both ideals of masculinity and femininity during times of war. These portrayals were part of wider conversations about gender and power, about the strength and weaknesses of women, and, ultimately, women's inferior status to men, which were utilised in allegorical forms to make claims to authority on these elite forms of male dress. 相似文献