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This paper describes a system of versatile software packages that has been developed by the author for population analysis on IBM-compatible microcomputers using PC or MS DOS. The series includes programs for the production of life tables, the analysis of spatial patterns and temporal trends in mortality, population projections, stationary-state population simulations and demographic planning, cohort survival estimates of net migration, and the analysis of migration matrices. Each of the programs in the series is discussed in terms of its principal analytical features, associated conceptual and methodological issues, and potential applications. The programs are intended for use both as basic research and planning tools and as instructional aids in university-level courses. The programs and related documentation are available on a set of four 360K diskettes.  相似文献   
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The measurement and interpretation of spatial economic structure have presented many problems for analysts. The notion of a spatial multiplier has received even less formal attention; part of the motivation for this paper is the examination of the degree to which sectoral decomposition analysis might prove useful in illuminating the paths of interaction across space that are associated with changes in exogenous activity levels. In this paper, we present three perspectives that examine spatial structure in the context of an aggregated interregional social accounting matrix for Bangladesh. These perspectives examine structure at the micro-, meso-, and macrolevels and are interpreted with the assistance of several alternative methods, including structural path analysis, the field of influence, the superposition principle, multiregional feedback loop analysis, and the Matrioshka Principle; the results are interpreted analytically and cartographically. Some attention is also devoted to the formulation of a general approach to spatial multipliers. It is shown that the structure of flows and the structure of influence reveal patterns that, taken together, provide important insights into an understanding of structure and may prove to form the basis for the eventual formal presentation of the spatial multiplier.  相似文献   
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A two-sector dynamic general equilibrium model is developed "to investigate the direction of migration in response to differing demographic and consumption demand behavior, as well as variations in production conditions." The model, which involves a rural sector and an urban sector, incorporates "returns to scale and the natural rate of sectoral population growth as important determinants of the direction of migration, in addition to price and income elasticities, and the sectoral technical change rate with which...previous studies dealt."  相似文献   
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Archaeology has been firmly embedded in the British planning systems for over a quarter of century, and development-led fieldwork is now by far the largest source of new information available to researchers. Custom and practice in the way that such work is conducted has evolved over this time, yet methodological innovation has been surprisingly limited. Using the data gathered in a major survey of the rural settlement of Roman Britain, this paper explores some themes in the way that commercial work is undertaken and seeks to open up a long-overdue debate about professional practice in a development-led context.  相似文献   
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Wang, Q., Wang, Y., Qi, Y., Wang, X., Choh, S.J., Lee, D.C. & Lee, D.J., November 2017. Yeongwol and the Carboniferous–Permian boundary in South Korea. Alcheringa 42, 245–258. ISSN 0311-5518

Six conodont and one fusuline zones are recognized on basis of a total of 25 conodont and 13 fusuline species (including seven unidentified species or species given with cf. or aff. in total) from the Bamchi Formation, Yeongwol, Korea. The conodont zones include the Streptognathodus bellus, S. isolatus, S. cristellaris, S. sigmoidalis, S. fusus and S. barskovi zones in ascending order, which can be correlated with the conodont zones spanning the uppermost Gzhelian to Asselian Age of the Permian globally. The fusuline zone is named the Rugosofusulina complicata–Pseudoschwagerina paraborealis zone. The co-occurrence of the conodont Streptognathodus isolatus (the Global Boundary Stratotype Section and Point index for the base of Permian) and Pseudoschwagerina (a Permian inflated fusuline) indicates that the Carboniferous–Permian boundary can be placed in the lower part of the Bamchi Formation in South Korea.

Qiulai Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yue Wang* [] LPS, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Yuping Qi* [] Xiangdong Wang* [] CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road 39, Nanjing 210008, PR China; Suk-Joo Choh [] Department of Earth and Environmental Sciences, Korea University, Seoul 02841, Republic of Korea; Dong-Chan Lee [] Department of Earth Sciences Education, Chungbuk National University, Cheongju 28644, Republic of Korea; Dong-Jin Lee [] Department of Earth and Environmental Sciences, Andong National University, Andong 36729, Republic of Korea. *Also affiliated with: University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, PR China.  相似文献   

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