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Environmental decision support systems (EDSS) are designed to assist natural resource managers and stakeholders to assess problems and select options for change. EDSS that combine community engagement in developing future scenarios with computer‐based land use planning and modelling tools are widely used internationally. However, these EDSS are often not used after the research and development phase. To best understand why the EDSS are not being used in the long term, the end users of the EDSS should be consulted—a perspective that is lacking in the literature. The research reported here presents the perspectives of stakeholders involved in a community climate change adaptation project in western Canada. Evidence from the community suggests that this project was successful in instigating change. However, the EDSS was not used after the project's end. Our findings indicate that, from the end users’ perspective, the project could have had much greater and sustained success had there been ongoing engagement and communication with them, particularly in the form of continued support for the use of EDSS after the development project.  相似文献   

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The image of writing is singularly frequent in cognitivistic explanations of the functioning of mind, not only as a metaphor but also as a conceptual paradigm: the Turing machine, particularly, displays a complete structural isomorphism with the use of alphabetical writing. The Turing machine performs exactly the same operations carried out by a man writing with pen and paper and this depends on two reasons: 1. it has been conceived in image and likeness of the human concrete practice of writing; 2. it is the typical product of the western rationality, whose development has been made possible only by the specific features of the alphabetical treatment of information. This is useful to understand why the mind started being depicted as a writing machine just when the alphabet began spreading: a genealogical investigation will show how in mnemotechnics treatises and in Plato's and Aristotle's metaphysics we can find the very first foundation of every logico-symbolical model of mind.  相似文献   

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The Minoan Terracotta pipes with their conical shape were widely used in the water distribution system in the ancient Minoan civilization. They remain one of the brightest achievements of the Minoan tribe in water supply technology and raise admiration as well as many questions about the technological advancements of antiquity, that are yet to be understood. The present work aims at answering the following questions: a) what inspired the Minoans to manufacture pipes with such a peculiar shape, that differs greatly not only from later pipe designs of antiquity, but also from contemporary cylindrical pipes and b) why was the design of those pipes abandoned after the fall of the Minoan civilization? It tries to address these questions by investigating the flow physics and dynamics that take place in such pipes, adopting advanced numerical and computational methods. The time-averaged Navier–Stokes equations along with the k − ? turbulence model are solved for a variety of geometrical parameters, pipe orientations and flow rates, in order to produce a comparative picture of the hydraulic efficiency of the conical Minoan pipes. The flow field is visualized and critical flow parameters, such as the head loss, the velocity magnitude and turbulence intensity, are calculated. These calculations show clearly that the conical Minoan pipes exhibit significantly higher pressure drops along their length compared to an equivalent straight pipe. In their widest part an extended recirculation appears, which could wash out impurities that may be present in the water, which at the same time cannot be deposited on the pipe wall. This evidence proves that the Minoan pipes are energetically expensive to operate and consequently their replacing by cylindrical pipes was inevitable. Therefore, it seems that the main advantage and purpose of the particular geometry was that they could be easily connected on site, forming long straight or slowly bending lines without having to add straight or many different fittings in between.  相似文献   

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This study develops a data analysis methodology for the exploration of the variance in chemical composition of ceramic artifacts due to their typological, location and temporal characteristics. This methodology then allows for the characterization of ceramics based on these characteristics and the sequential assignment of unclassified ceramics to a region, subregion or site, with further assignment to specific ware and chronological period. The procedure uses INNA data on the elemental composition of ceramics in order to derive a series of classification functions for each category within each level of the taxonomic hierarchy. The developed procedure is used to investigate a provenance problem involving Chalcolithic ceramics from the Zagros region of western Iran. The results show that the elemental composition of ceramics, when coupled with multivariate statistical techniques, represents a powerful means for distinguishing ceramic provenance.  相似文献   

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Substantial changes to the built environment, urbanisation patterns, and societal norms have contributed to limiting children's opportunities for being independently mobile. Several linear causal pathway models have been developed to understand the influences on children's independent mobility; however feedback loops between and within the various levels of influence cannot be modelled using such an approach. The purpose of this paper is to refine the interrelationships of factors related to children's independent mobility, taking into account earlier models, broader contextual factors, recent children's geographies literature, and feedback loops. Systems model components were informed by attributes known to influence children's independent mobility, related qualitative findings, and the development of a framework that could lend itself to multilevel modelling approaches. This systems model may provide a useful structure for identifying how best to develop and monitor interventions to halt the declining rates of children's independent mobility.  相似文献   

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Ugan, Bright and Rogers [When is technology worth the trouble? Journal of Archaeological Science 30 (10) (2003) 1315–1329] develop procurement and processing versions of an optimization model, termed the tech investment model, to formalize the conditions that favor investing time in the manufacture of more productive but more costly technologies. Their approach captures the tradeoffs that occur as less costly versions are supplanted by more costly versions of the same category of technology (e.g., fishhooks), but not the tradeoffs that occur when more costly categories of technology supplant different but less costly categories used for the same purpose (e.g., hook and line vs. spear). We (i) propose an alternative model in which different categories of technology are characterized by separate cost–benefit curves, (ii) develop point-estimate and curve-estimate versions on this model, and (iii) show how they might be applied using the development of weaponry in aboriginal California as an example.  相似文献   

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In this paper, a lightning channel is simulated by a vertical wire of finite length and of moderate electric conductivity. At low frequencies, such a wire behaves like a resonant wave guide cavity in which only discrete resonant wave modes can be generated. The theory of resonant waves in a wire of finite diameter is outlined and applied to the return stroke with electric contact to the earth and to intracloud K-strokes without electric contact to the earth. Two types of current wave forms exist: aperiodic waves of the Bruce-Golde type and damped oscillations. The configurations of the electric charge density and the electric current in the wire are presented for the various wave modes as functions of height and time. From the observations of lightning current and of sferic wave forms, it is apparent that the first mode dominates, and that both types of wave forms can be identified. From these wave forms, the channel parameters-length and diameter can be derived. For the higher order modes, the resonance model loses its validity and freely propagating waves are expected during the whole lightning flash. These waves contribute to the observed continuous spectrum. The skin effect becomes important increasing the effective resistance of the wire with frequency. Since these waves interfere destructively, they do not contribute significantly to an effective charge transport.  相似文献   

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How do votes disperse through a territory? Studies of spatial voting patterns have largely focused on the influence of local factors on voting. The “Friends and Neighbors” model (Key (1949)) explains the advantage of candidates running for office in the locality with which they are associated (Arzheimer and Evans (2012, 2014): Collignon and Sajuria (2018); Horiuchi et al. (2018); Jankowski (2016); Hunt (2020); Munis (2021)), and the “neighbor” effect helps to explain why votes spread. More recent studies have found that the dispersion of votes decreases with distance (Put et al. (2020); Arzheimer and Evans (2012)). However, we know little about how spatial patterns of voting emerge or the mechanism behind the neighbor effect. We argue that this effect depends on the neighbors’ access to information about a candidate, which is constrained by the way information flows. Although scholars have argued that information is a relevant driver explaining the dispersion of votes (Bowler et al. (1993); Arzheimer and Evans (2012); Evans et al. (2017); Campbell, Cowley, Vivyan, and Wagner (2019)), no research has examined the relevance of the network through which information flows. We propose that a spatial interaction model (Wilson (1971)) allows us to predict where this information flows or the voting pattern that will form. Taking advantage of a quasi-natural experiment in Brazilian legislative elections in 1974 and 1978, we show that votes spread through areas of influence created by a hierarchy of cities based on the flows of exchanges among them, including information. We then use our spatial interaction model to predict voting patterns in the elections of 1978 using data from the 1974 elections. Our findings show that the spatial interaction model results fit the data quite well and can help predict spatial patterns of voting.  相似文献   

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A recursive model of the spatial allocation of migrants   总被引:1,自引:0,他引:1  
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Selective resource exploitation patterns in prehistory are often explained in terms of cultural preference, but this paper argues that a non-cultural explanation based upon zoological models of consumer choice may be equally valid. A model of shell-fishing behaviour concerning the relationship of abundance and yield is developed and used to predict that rocky shore collectors should ignore all factors other than the individual size of shellfish and that, in doing so, they would become progressively selective in their collecting patterns. Data from prehistoric rocky shore shell middens in Palliser Bay, New Zealand, indicates several phases of progressively selective collecting over a period of 600 years and these patterns appear best explicable in terms of the model.  相似文献   

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"This paper presents a two-sector dynamic model of regional population change. The model contains a migration equation, an earnings equation, and an amenity equation for each region. In the context of this model, migration is seen as a disequilibrium process through which the regional populations move towards equilibrium positions. Migration occurs when one region is perceived to be superior to the other on the basis of its earnings and amenity levels. Equilibrium is achieved when population movements between the regions eliminate any differences in their relative attractiveness. A comparative-static analysis of the model is presented to analyze the effects of policy changes and exogenous shocks on the distribution of population among the regions." The geographical focus is on the United States.  相似文献   

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A new method for modelling archaeological resource potential is presented that avoids some of the mathematical violations and inconsistencies of previously-favoured techniques. The Minanha research area in west-central Belize and a database of other Maya centres from within Belize are used as a case study for demonstrating the utility of the proposed modelling technique.  相似文献   

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This paper describes the experimental model that formed the basis for the author's PhD thesis. The main goal of the work is the implementation of Geographic Information Systems (GIS) in archaeological research. A survey of the state of the art was undertaken to enable an assessment of the model to be tried out and how implementation should be undertaken. The problem encountered then, and which still persists, is that data that are sufficiently reliable for archaeological purposes are hard to come by, in digital format.  相似文献   

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A review of (almost) 20 years of regional innovation systems research   总被引:1,自引:0,他引:1  
ABSTRACT

The literature on regional innovation systems (RISs) has grown impressively in the last two decades. The objective of this study is to provide a comprehensive assessment of all RIS articles published in scholarly journals between 1998 and 2015. It aims to inform researchers of the empirical results obtained so far and highlight areas that need further work. This review describes how the RIS field has developed, charts the current body of RIS research and discusses recommendations for moving the RIS field forward.  相似文献   

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