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The article examines the extent to which Vietnam, Laos and Cambodia have gained from their participation in ASEAN. To assess the security and diplomatic benefits of their membership, it identifies three expectations held by the Indochinese states—enhanced international status, improved security and relations vis-à-vis other ASEAN members, and more room for manoeuvre when dealing with non-member states. The study demonstrates, however, that while Vietnam, Laos and Cambodia are less isolated internationally after joining ASEAN, the actual benefits in terms of their relations with the other ASEAN members as well as non-member states have been more ambiguous. With ASEAN in mind, the article concludes by discussing the possible costs and drawbacks of enlargement that can transform any international organisation into a less influential and cohesive institution.  相似文献   
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Well constrained numerical ages of alluvial fan sediments are key to understanding the chronology of alluvial episodes and tectonic activity at the front of the Andean Precordillera. We tested the application of radiocarbon and optically stimulated luminescence (OSL) dating in the distal part of an alluvial fan five kilometers north of Mendoza. For OSL dating a large number of aliquots (n > 70) — each composed of ∼50 quartz grains — were measured in order to obtain reliable burial ages despite scattered dose distributions. Owing to a feldspar contamination in all samples, an infrared stimulation was inserted before each OSL measurement, which reduced the feldspar OSL signal successfully. By using the minimum age model we obtained stratigraphically consistent burial ages of alluvial deposits in a depth profile. The uppermost ∼1 m of sediment is composed of debris flow deposits buried 770±76 years ago. Three plant remnants used for radiocarbon dating from the same layer, however, yielded ages younger than 350 years, which are interpreted to underestimate the depositional age. Underneath the debris flow, a major unconformity cuts a series of distal alluvial fan sediments with interstratified floodplain deposits, which are composed of sandy and calciterich silt layers, respectively. Three samples from this unit which were distributed over one meter of sediment thickness yielded statistically concordant OSL ages of 12.3±1.2 ka, 12.3±1.2 ka, and 11.7±1.1 ka. The deposition of these sediments during the latest Pleistocene coincides with a phase of cool and humid climate, which occurred before the alluvial fan propagated farther into the foreland. The overlying debris flow sediments are associated with alluvial fan incision during the arid Late Holocene.  相似文献   
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A recently published paper proposing a “strict solar alignment” of figurative rock carvings in southern Sweden requires some critical and cautionary remarks. Using the paper “Strict solar alignment of Bronze Age rock carvings in SE Sweden” by N.-A. Mörner as a case study, various pitfalls and challenges in archaeoastronomical investigations are highlighted. Substantiating the idea of a relationship between the orientation of archaeological features such as rock carvings and astronomical events such as sunrise at winter solstice requires accurate and precise determination of (i) the orientation of the archaeological features and (ii) the azimuth of the astronomical event at the time of creation of the rock carvings, taking into account all influencing factors such as changes in Earth orbit parameters, surrounding topography and vegetation. Furthermore, possible motivations or intentions of Bronze Age rock carvers have to be considered. When trying to support a causal link between the orientation of archaeological features and astronomical events, it is indispensable to discuss and exclude possible alternative explanations, related to, for example, rock carving practice and visibility. Taking into account the above issues, there is no evidence for a solar alignment of the Järrestad rock carvings. The issues discussed using the Järrestad rock carvings as a case study are relevant to archaeoastronomical investigations in general.  相似文献   
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This essay explores the dilemmas associated with ‘squaring the circle’ of wealth creation, social cohesion and political freedom in the OECD countries. As the metaphor of square and circle implies, these three essential goals of development are not necessarily compatible and may even conflict with each other, particularly at a time when advancing globalization creates perverse choices. To become and remain competitive in international markets requires a flexible use of resources which threatens social cohesion and political freedom in a number of ways. After analysing these tensions, the essay concludes with six proposals for improving the likelihood that a workable balance between prosperity, democracy and social cohesion can be maintained in advanced industrial societies.  相似文献   
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Success or failure of a polycentric system is a function of complex political and social processes, such as coordination between actors and venues to solve specialized policy problems. Yet there is currently no accepted method for isolating distinct processes of coordination, nor to understand how their variance affects polycentric governance performance. We develop and test a building-blocks approach that uses different patterns or “motifs” for measuring and comparing coordination longitudinally on Australia's Great Barrier Reef. Our approach confirms that polycentric governance comprises an evolving substrate of interdependent venues and actors over time. However, while issue specialization and actor participation can be improved through the mobilization of venues, such a strategy can also fragment overall polycentric capacity to resolve conflict and adapt to new problems. A building-blocks approach advances understanding and practice of polycentric governance by enabling sharper diagnosis of internal dynamics in complex environmental governance systems.  相似文献   
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