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21.
New World States and Empires: Politics, Religion, and Urbanism 总被引:2,自引:0,他引:2
The past decade has seen a veritable explosion in archaeological research on complex societies in Latin America. In 1993, Smith published an overview of research to that date; this article is one of two bringing that summary up to the present. Our first article, New World states and empires: Economic and social organization (Smith and Schreiber, 2005), dealt with issues regarding economic and social organization. The present article tackles political organization and dynamics, religion, urbanism, and settlement patterns. We also review recent research in the context of various theoretical perspectives, some traditional, some more contemporary, including approaches to history and process, cultural evolution, agency-based models, linguistic prehistory, migration theory, and the relationship between environmental change and cultural events. Our discussion blends empirical findings, methodological advances, and theoretical perspectives. 相似文献
22.
唐前期的地方监察体制由御史和诸道使臣组成,属于朝廷派出性质的单一型监察体制。安史之乱以后,伴随赋役制度的改革,出使郎官、转运使、巡院等新的监察体系出现,我国封建社会地方监察体制开始向固定型、多元化、多层面变革,宋代完成了这一变革。元、明、清各朝基本延续和发展了宋代多元化、多层面的地方监察体制。由此而论,唐宋地方监察体制变革是我国封建社会地方监察制度前后两期的分界线。 相似文献
23.
John Kantner 《Journal of Archaeological Research》2008,16(1):37-81
In the 1970s and 1980s, regional analysis was an influential part of archaeological research, providing a discrete set of
geographical tools inspired by a processual epistemological and interpretive perspective. With the advent of new technologies,
new methods, and new paradigms, archaeological research on regional space has undergone significant changes. This article
reviews the state of regional archaeology, beginning with a consideration of its history and a discussion of the fundamental
issues facing regional investigations before focusing on developments over the last several years. On one hand, the diversification
of archaeological theory has created new paradigms for thinking about human relationships with one another and with the physical
environment across regional space; in this regard, historical ecology, landscape archaeology, and evolutionary theory have
been particularly influential in recent years. This has led to a corresponding diversification of the traditional methods
of regional analysis. Most notably, the advent of powerful digital technologies has introduced new tools, especially those
from the geographic information sciences, that build on the quantitative methods of past approaches. The investigation of
regional data is no longer based on a discrete toolkit of simple mathematical and graphical procedures for representing spatial
relationships. Instead, regional archaeology has matured into a diversity of multiscalar spatial and geostatistical techniques
that inform many areas of archaeological inquiry. 相似文献
24.
Two‐phase flow and near‐critical phenomena are likely to enhance energy transport in high‐temperature hydrothermal systems. We present a series of two‐dimensional simulations of two‐phase flow of pure water at near‐critical conditions. The results show that at near‐critical conditions, two‐phase convection can be more efficient in transporting energy than single‐phase convection. The highest heat fluxes are attained when two‐phase heat‐pipes form near the bottom boundary, recharging the root of the upflow zone and thereby enabling the formation of broad upflow regions. When the system becomes more vapor‐dominated, it loses this ability, upflow zones become narrower and the energy efficiency drops to more moderate values. 相似文献
25.
The Krafla geothermal system is located in Iceland's northeastern neovolcanic zone, within the Krafla central volcanic complex. Geothermal fluids are superheated steam closest to the magma heat source, two‐phase at higher depths, and sub‐boiling at the shallowest depths. Hydrogen isotope ratios of geothermal fluids range from ?87‰, equivalent to local meteoric water, to ?94‰. These fluids are enriched in 18O relative to the global meteoric line by +0.5–3.2‰. Calculated vapor fractions of the fluids are 0.0–0.5 wt% (~0–16% by volume) in the northwestern portion of the geothermal system and increase towards the southeast, up to 5.4 wt% (~57% by volume). Hydrothermal epidote sampled from 900 to 2500 m depth has δD values from ?127 to ?108‰, and δ18O from ?13.0 to ?9.6‰. Fluids in equilibrium with epidote have isotope compositions similar to those calculated for the vapor phase of two‐phase aquifer fluids. We interpret the large range in δDEPIDOTE and δ18OEPIDOTE across the system and within individual wells (up to 7‰ and 3.3‰, respectively) to result from variable mixing of shallow sub‐boiling groundwater with condensates of vapor rising from a deeper two‐phase reservoir. The data suggest that meteoric waters derived from a single source in the northwest are separated into the shallow sub‐boiling reservoir, and deeper two‐phase reservoir. Interaction between these reservoirs occurs by channelized vertical flow of vapor along fractures, and input of magmatic volatiles further alters fluid chemistry in some wells. Isotopic compositions of hydrothermal epidote reflect local equilibrium with fluids formed by mixtures of shallow water, deep vapor condensates, and magmatic volatiles, whose ionic strength is subsequently derived from dissolution of basalt host rock. This study illustrates the benefits of combining phase segregation effects in two‐phase systems during analysis of wellhead fluid data with stable isotope values of hydrous alteration minerals when evaluating the complex hydrogeology of volcano‐hosted geothermal systems. 相似文献
26.
DAVID TURNBULL 《Geographical Research》2007,45(2):140-149
If maps are conceived as representations of reality or as spatially referenced data assemblages, a dilemma is raised by the nature of Indigenous knowledge traditions and multiple ontologies. How can differing knowledge traditions, differing ways of mapping be enabled to work together without subsumption into one common or universal ontology? The paper explores one way of handling this dilemma by reconceiving mapping and knowing performatively and hodologically. It is argued that one way in which differing knowledge traditions can interact and be mutually interrogated is by creating a database structured as distributed knowledge and emulating a complex adaptive system. Through focusing on the encounters, tensions and cooperations between traditions and utilising the concept of cognitive trails‐ the creation of knowledge by movement through the natural and intellectual environment – the socially distributed performative dimensions of differing modes of spatially organised knowledges can then be held in a dialogical tension that enables emergent mapping. 相似文献
27.
兰作为一种人格的象征,它的内涵是多重的,自孔子对它的化内涵作了人格化定位后,它显示了自身的延展性,在不同的化背景下对儒学人格进行调整、补充。而图腾崇拜的心理机制,又使兰在儒学人格的象征谱系中始终占据着“王”的地位,体现了儒学中浓厚的“兰情结”。 相似文献
28.
Salomon Orellana 《政策研究杂志》2010,38(4):613-628
This paper argues that in certain areas of policy, electoral systems can influence policy innovation (how early countries will adopt certain policies). Electoral systems influence the number of parties that win representation and thereby influence the diversity of perspectives included in the policymaking process. It is argued here that this diversity facilitates elite and public consideration of new issues and ideas, and consequently, it leads to earlier debate and action on these issues and ideas. This dynamic is particularly relevant to controversial issues and ideas that major parties may be hesitant to address and that minor parties may be more incentivized to promote. In this paper, two issues/ideas are considered: extending rights to same‐sex couples and making material sacrifices to protect the environment. I show that countries with more proportional electoral systems tend to act earlier to protect the environment and that they tend to be early adopters of civil union legislation. These results are also supported by World Values Survey data showing public preference patterns that support these policy outcomes. 相似文献
29.
Calculations are presented of the extent to which chemical disequilibria are generated when submarine hydrothermal fluids mix with sea water. These calculations involve quantifying the chemical affinity for individual reactions by comparing equilibrium compositions with the compositions of mixtures in which oxidation–reduction reactions are inhibited. The oxidation–reduction reactions that depart from equilibrium in these systems provide energy for chemotrophic microbial metabolism. Methanogenesis is an example of this phenomenon, in which the combination of carbon dioxide, hydrogen and methane induced by fluid mixing is far from equilibrium, which can be approached if more methane is generated. Similarly, the production of other organic compounds is also favorable under the same conditions that permit methanogenesis. Alkanes, alkenes, alcohols, aldehydes, carboxylic acids and amino acids are among the compounds that, if formed, would lower the energetic state of the chemical composition generated in mixed fluids. The resulting positive values of chemical affinity correspond to the thermodynamic drive required for abiotic organic synthesis. It is also possible that energy release accompanies biosynthesis by chemotrophic organisms. In this way, hydrothermal ecosystems differ radically from familiar ecosystems at Earth's surface. If captured, the energy released may be sufficient to drive biosynthesis of carbohydrates, purines, pyrimidines and other compounds which require energy inputs. 相似文献
30.
M. G. Blöcher G. Zimmermann I. Moeck W. Brandt A. Hassanzadegan F. Magri 《Geofluids》2010,10(3):406-421
Understanding hydrothermal processes during production is critical to optimal geothermal reservoir management and sustainable utilization. This study addresses the hydrothermal (HT) processes in a geothermal research doublet consisting of the injection well E GrSk3/90 and production well Gt GrSk4/05 at the deep geothermal reservoir of Groß Schönebeck (north of Berlin, Germany) during geothermal power production. The reservoir is located between ?4050 to ?4250 m depth in the Lower Permian of the Northeast German Basin. Operational activities such as hydraulic stimulation, production (T = 150°C; Q = ?75 m3 h?1; C = 265 g l?1) and injection (T = 70°C; Q = 75 m3 h?1; C = 265 g l?1) change the HT conditions of the geothermal reservoir. The most significant changes affect temperature, mass concentration and pore pressure. These changes influence fluid density and viscosity as well as rock properties such as porosity, permeability, thermal conductivity and heat capacity. In addition, the geometry and hydraulic properties of hydraulically induced fractures vary during the lifetime of the reservoir. A three‐dimensional reservoir model was developed based on a structural geological model to simulate and understand the complex interaction of such processes. This model includes a full HT coupling of various petrophysical parameters. Specifically, temperature‐dependent thermal conductivity and heat capacity as well as the pressure‐, temperature‐ and mass concentration‐dependent fluid density and viscosity are considered. These parameters were determined by laboratory and field experiments. The effective pressure dependence of matrix permeability is less than 2.3% at our reservoir conditions and therefore can be neglected. The results of a three‐dimensional thermohaline finite‐element simulation of the life cycle performance of this geothermal well doublet indicate the beginning of thermal breakthrough after 3.6 years of utilization. This result is crucial for optimizing reservoir management. Geofluids (2010) 10 , 406–421 相似文献