Interregional Migration Modeling via Entropy and Information Theory

In attempting to model gross migration flows, as distinct from net flows, entropy and information theory models supplement those from the demographic tradition. However, clear differences exist between these two classes, including the type of origin and destination information which needs to be supplied, the relationship between the overall decision to migrate and the conditional choice of destination, the role of behavioral variables other than distance, and the expected predictive performance. In this paper, an enhanced interregional migration model is introduced which attempts a further integration of both the above classes. A linear version of the model is used for exploratory data analysis on a large Australian population census data set. Several alternative hypotheses are then tested with the general model. Some guidelines are also indicated toward developing a fully dynamic version of the model as well as a formal hierarchical framework.     

自然疆界论的话语建构与时空延异

中国学术界往往将法国大革命时期著名政治活动家丹东作为自然疆界论的始作俑者或代表人物,对自然疆界论的了解亦多源自法国大革命历史论著中片言只语的叙述.自然疆界论是流质性的法国政治文化中不断呈现的富有能量的表象.自然疆界的含义变动不居,本文依照长时段的研究路径而从政治学、社会学的视野分析自然疆界论在不同历史时期的话语建构.     

Modeling Bikeability of Urban Systems

There are characteristics of urban transportation infrastructure that are thought to influence use by bicyclists given their perceived effect on safety, comfort, and efficiency. Prior research has primarily focused on assessing the qualities of individual road segments and analysis of one or a few routes connecting pairs of origins and destinations (ODs). To address these limitations, a multicriterion shortest path framework is proposed for evaluating the characteristics of alternative routes and measuring their tradeoffs with respect to three routing objectives. A label correcting algorithm is described for identifying the complete set of routes optimizing the three objectives and metrics are developed to summarize variations in bikeability within an urban environment. The proposed methods are applied to a case study involving 27,722 urban ODs, yielding 329,931 paths optimal with respect to some combination of the three routing objectives. In particular, 77,418 paths (23.5%) were found to optimize one or more of the three individual routing objectives while 252,513 paths (76.5%) were found to optimize some tradeoff among the three routing objectives. This large number of Pareto‐optimal tradeoff paths underscores the importance of not limiting analysis of routing alternatives to one or two individual objectives.     

Plant Communities and the Dynamics of Natural Systems

Plant communities are viewed as a factor of both stabilization and transformation of natural systems. Two categories of subdivisions of the plant cover are distinguished: phytocenomers, which are the object of vegetation classification, and phytocenochores, which are units of geobotanic regionalization. The two categories are compared at the planetary, regional, and topologic levels. A plant association is viewed as a dynamic system building up through a series of variable structures to the ultimate indigenous, invariant, climax structure. The evolution of an association is depicted in the form of a graph, in which the vertices designate the various states leading to the climax association, and the edges the probable transitions from one state to another. The graph is plotted on a system of coordinates reflecting both the time period of these transformations and their effect (in terms of increases or decreases of the total plant mass). The technique is illustrated with two specific associations: the forb-tyrsa association of the Transbaykal steppe, and the fir, low-grass, green-moss association of the southern tayga (boreal forest).     

考古学研究中的系统论

本文发表于1975年,其时新考古学作为一种划时代的思潮已经取得了历史性成就。新考古学家们为新的研究目标,从其它学科中引进了许多新的思想和方法,系统论作为其中最重要的理论方法之一,开始取代文化历史考古学中的关键学术概念和分析单位——考古学文化(当然,系统论作为人类思想领域的最新成果,对自然科学和社会科学的各个门类都产生了重要和深刻的影响,而决非仅限于考古学)。并成为考古学理论方法变革的一个重要标志。系统论的精髓在于将考古学从立足于器物静态的分析和分类以及编史学的研究,转向对这些器物制作和使用的人类行为和适应环境等多变量互动系统关系的阐释。考古学文化不再被看作是分析的基本单位和关键概念,而是需要从物质遗存产生的背景和各种因果关系来了解文化的产生和演变,并对考古学研究的概念、方法以及探讨和力求解决的问题做根本的调整。这使得考古学家能够放弃过去那些无法解决或意义不大的问题,将精力集中到更加便于观察和更加容易解决的问题上。本文通过对沃森、勒布朗和雷德曼、克拉克和弗兰纳里等学者有关成果的叙述,详细介绍了系统论引入考古学的起因、过程和发展,从概念的革新和建模方式等方面,阐述了系统论对考古学研究革命性的影响,以及在人类学、民族学等考古学相关领域内所引起的变革。可以说,现代考古学理论相对于经典考古学所取得的突破性的成就,很多方面都是引入系统论思维的结果。阅读本文,虽然作者写作的对象是西方学者,中国读者由于对许多背景知识不是很了解,在翻译和阅读上可能会出现一些困难,但是仔细领会其中一些要点,还是能够帮助我们对系统论的意义有一个初步的了解。     

On Modeling the Evolution of Hunter-Gatherer Decision-Making Systems

Models of both primate and hunter-gatherer decision-making systems are developed and their relative abilities potentially to detect certain classes of spatial distributions within a standardized environment are compared. It is demonstrated that in situations where language facilitates the pooling of information between individuals within a hunter-gatherer group, the group minimally need only to pool information with one central decision maker in order potentially to recognize all possible spatial distributions within a limited environment. On this basis alone, we would theoretically expect the presence of one-leader groups to be a fairly ubiquitous phenomenon among hunter-gatherers.     

鄂尔多斯高原自然背景和明清时期的土地利用

鄂尔多斯高原位于我国北方沙漠-黄土边界带的关键位置上,通过百年来沙漠-黄土边界带概念的形成考察,从学术史上获得该论题蕴含有过渡带、敏感带、生态交错带内涵,这是众多学科研究意义所在。明代为防御元蒙势力,沿长城地带实行军屯,清代限于人口压力和财政因素,从长城内到长城外,将"变刍牧而桑麻"的活动扩展到大半个高原。汲取学术界已有成果,尤其是以长城作为判断毛乌素沙地南移及其与明清垦殖活动关系的一种考察方式,在影响毛乌素沙地的走向和幅度上,认为自然因素更显重要。尽管人类利用土地的形式和规模在逐渐升级,但在明清时期的演变过程中,仍只是作为荒漠-草原彼此进退的一种参与力量。     

The Present State and Future Tasks in the Theory and Method of an Evaluation of the Natural Environment and Resources

The needs of optimal resource development policy in the Soviet Union have given rise to a new interdisciplinary research discipline concerned with the evaluation of the physical environment and natural resources. Evaluations are made of particular environments or resources or an integrated natural complex as a whole (the “object” of the evaluation) from the point of view of particular elements of society or society as a whole (the “subject” of the evaluation). Evaluations may be in terms of social utility, economic cost, technological feasibility, or medical-biological requirements. A number of methodological problems remain to be solved in evaluative research: (1) comparability between evaluations of particular elements and of integrated environments or resource complexes, (2) commensurability of various categories of evaluation (social, economic, technological) of a particular type of environment or resource, (3) the problem of weighting individual elements in integrated evaluations; and (4) the question of converting physical measurements into evaluations on a point scale.     

Recent Directions and Developments in Geographical Information Systems

Geographical information systems (GIS) are tools for handling and processing spatially referenced information that have permeated all facets of archaeology, frequently revolutionizing research by allowing easy access to vast amounts of information, new ways of data visualization that promote insight through pattern recognition, and unique methodologies that allow entirely new approaches to the study of the past. This comprehensive review examines and critiques recent advances achieved through GIS in regional and within-site databases, locational analysis and modeling, regional simulation, studies of landscape perception through intervisibility analysis, and models of spatial allocation, territoriality, and site access. The future prospects of GIS are enormous with the growth of the Internet, the resultant linking of databases, expected enhancements in satellite remote sensing, and the increasing pervasiveness of global positioning systems for spatial data capture. If there is a persistent theme that emerges from the chronicles of contemporary scientific cartography, it is that the creation of a map almost inevitably leads to unexpected revelations. — Hall, Mapping the Next Millenium: How Computer-Driven Cartography Is Revolutionizing the Face of Science     

Systems Theory and Skeptical Humanism in French Ecological Thought

In systems theory, nature appears as an intricate interweaving of homeostatic processes–processes that mankind disrupts at its own peril. For many non-French ecologists, only respecting nature's "intrinsic value" will avert catastrophe. Such reasoning is rare in France. In its place, theorists like Edgar Morin and Michel Serres promote a systems-inspired ecologism that skirts the problematic dualism of nature and humanity by questioning skeptically how we understand both the world and ourselves.     

Modeling Distance Decay Effects in Web Server Information Flows

Previous studies have shown that there is a direct correlation between the popularity of a medium and the cost in transmitting information through that medium. On this basis the World Wide Web may become more important as a mass medium than radio and television. Yet despite the enormous growth in Internet information and Internet-supported businesses, there has been, as yet, little in the way of quantitative spatial analysis of information flows on the WWW. One major issue is whether or not distance influences the web sites that a user may visit. If distance is a factor, then the location of servers delivering content becomes important. In this paper an analysis of information flows from U.K. academic web servers to the rest of the world is carried out. Using a UNIX utility called ping, the average time taken for a defined amount of information to travel between the United Kingdom and sixty-six other countries across the Internet was measured. This time measurement known as latency is used as a measure of distance on the Internet. The latency measurements are combined with counts of visitors from each of these countries to approximately one hundred U. K. academic WWW servers and used to build a simple gravity model of WWW information flows. The latency measurements between the United Kingdom and the other countries were gathered over a week in 1996. The counts of visitors relate to the total number of visits to the web servers over various time-scales for the years 1995 and 1996. We make the assumption that the distance measurements used are relevant to the visit counts. We also assume that all visitors from the .edu domain are geographically located in the United States. The gravity model is used to determine the effect of Internet distance on the number of expected visits to a web server. The study shows that latency values are a useful metric for measuring Internet distance. The results also demonstrate that the number of visitors to a web site falls off with distance on the Internet, as measured by latency values.     

Natural Law Theory,Legal Positivism,and the Normativity of Law

This essay examines two dominant traditions in legal philosophy, the natural law theory and legal positivism, in terms of how they account for the normativity of law. I argue that, although these two traditions generally take the question of the normativity of law seriously and try to account for it, they are not successful in doing so. This failure in the prevailing literature on the philosophy of law, I suggest, nevertheless has an implicit reconstructive impact: the insights into the failure of natural law theory and legal positivism imply an alternative philosophical framework that may provide a positive answer to the question of the normativity of law.     

Teaching Geographic Information Systems in a Problem-Based Learning Environment

How, where and why GIS is taught has been debated heavily in the geography literature. This article is a contribution to that debate, because it offers a new perspective from which to teach GIS: problem-based learning. In a problem-based learning classroom, theoretical foundations and the real world of problems are understood as constitutive of one another, rather than theory being prioritised over the real world of experience. In this paper, the author describes an introductory-level GIS class in which GIS was taught with a problem-based learning pedagogy. The problem around which the class focused was a proposal to add a new school district in the San Antonio, Texas metropolitan region. This article describes the class, including the nature of the problem and the way GIS skills were sequentially taught and integrated into the analysis of that problem.     

The Present State of the Natural Environment in Europe

The impact of industrialization and urbanization on the natural environment of Europe is analyzed and compared on the basis of regional reports submitted by 15 nations to the 1968 Unesco conference on the resources of the biosphere. For purposes of analysis, the nations of Europe have been grouped into capitalist countries, the socialist countries of Central and Eastern Europe, and the USSR. All of them are found to be affected by the same problems of increasing volumes of industrial and municipal wastes, a drift of population to the cities and growing air and water pollution. But the socialist nations are said to be distinguished from the capitalist countries in implementing systematic government control over all forms of pollution, providing recreational zones for the population at large, expanding a network of natural areas with conservation and amelioration of flora and fauna, and carrying out a broad program of transformation of nature designed to make optimal use of resources and to conserve and ameliorate the environment.     

自然灾害与自然条件对困难时期饥荒形成的影响

困难时期的大饥荒 ,尽管主要是人为错误带来的恶果 ,但是 ,从实事求是的态度出发 ,不应该夸大也不应该否定自然灾害的影响。根据计算结果 ,1 961年的人口损失比较明显地受到自然灾害的影响。由于自然条件的差异 ,条件差的地区人口损失更为严重。