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141.
ABSTRACT. This paper examines the RAS, Mc Menamin and Haring, and Lagrange-multiplier update methods in the context of the dual accounting system of the rectangular input-output model. The motivation was to determine if the additional information contained in the dual system is exploitable, while maintaining the integrity of the rectangular structure with all its advantages. Tests were conducted on the performance of the various algorithms for a derivative Leontief model relative to their performance on the rectangular structure. The results obtained for rectangular tables were generally better than those obtained for the more conventional Leontief ones.  相似文献   
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Reviews     
Babi and Baha'i Religions: From Messianic Shi'ism to a World Religion, by Peter Smith, Cambridge University Press, London, New York, New Rochelle, Melbourne, Sydney 1987, pp.xiv, 243.

Panj Vaqf‐namah, by Mahmud Afshar Yazdi, (Five Endowment Deeds), Tehran Foundation for Mahmud Afshar Yazdi's Endowments, 1363/1984. Iraj Afshar and Karim Isfahaniyan, eds., Namvarah‐yi Doktor Mahmūd Afshar Yazdi (Mahmud Afshar Yazdi's Festschrift), 4 vols., Tehran: Foundation for Mahmud Afshar Yazdi's Endowments, 1364/1985–1367/1988.

Bulles et Sceaux sassanides de diverses collections, by Philippe Gignoux and Rika Gysclen, Paris: Sludia Iranica, Cahier 4, Association Pour l'avancemeni des études iraniennes, 1987, 306 pp, 23 plates.

Iran and Iraq at War , by Shahram Chubin and Charles Tripp, Boulder, Colorado: Westview Press, 1988.

The Tragedy of Sohrab and Rostam, from the Persian National Epic, the Shahnameh of Abol‐Qascm Ferdowsi, translated by Jerome W. Clinton, Seattle: The University of Washington Press, 1988, xxv + 190 pages, $25.00 cloth $12.50 paper.

Persian Carpets , by Michael Craig Hillmann, Austin: University of Texas Press, 1984, 98 pp. index to p. 112.

Resurrection and Renewal: The Making of the Babi Movement in Iran, 1844–1850, Abbas Amanat, Ithaca & London: Cornell University Press, 1989, pp. xv.+ 461, no price indicated.

Iran min al‐Dakhil, (Iran From Within), by Fahmi Huwaydi, Cairo: Markaz al‐Ahram li al‐tarjuma wa al‐nashr, 1987, 405 pp.

Woven From the Soul, Spun from the Heart: Textile Arts of Safavid and Qajar Iran, 16lh‐19lh Centuries , edited by Carol Bier, Washington, DC: The Textile Museum, 1987.

Summon Up Remembrance, by Marzich Gail, Oxford: George Ronald Books, 1987, 295 pp., appendix, bibliography, $14.95.

Iran and The United States, A Cold War Case Study, by Richard W. Cottam, Pittsburgh: University of Pittsburgh Press, 1988. $12.95 pb.  相似文献   

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This paper has two main objectives. First, we review and evaluate four different computational methods for measuring the “fractality” of cartographic lines: these are known as the structured walk, the equipaced polygon, the hybrid walk, and the cell count methods. Second, because previous research has restricted the focus of fractal measurement exercises to isolated physical entities, the subject of our empirical study concerns the urban area of Swindon, United Kingdom, that comprises a mosaic of contiguous land-use parcels. In technical terms, the results pinpoint some of the comparative strengths and weaknesses of the four methods, whilst our substantive conclusion is that fractal dimension appears to be a function of both scale and land-use type in our geographical study.  相似文献   
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An axiomatic approach to distance is developed which focuses on those behavioral concepts of distance related to movement in space. In particular, spatial movement by behaving units is postulated to involve a choice from among some set of abstract trips in space, and implicitly, to involve the minimization of some relevant notion of trip costs. In this context, the relevant behavioral notion of distance in space is taken to be the minimum-cost distance generated by this choice process. These trip-cost concepts extend the classical notions of paths, path lengths, and shortest paths in metric spaces. Hence many of the analytical results of the paper involve extensions of classical shortest-path distance properties to minimum-cost distances. In addition to these extensions, a characterization theorem is given which specifies the possible functional relationships between trip costs and their associated path lengths. These relationships include most functional forms which are commonly employed in the literature.  相似文献   
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