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31.
Rapid urbanisation and climate change have motivated the development of urban green infrastructure (UGI) as a planning strategy to support the wellbeing of urban people and ecosystems while parallel adapting cities to climate change. Forest (tree-covered areas >0.5 ha) is a key UGI component that afford a wider range of ecosystem services and mitigate urban heat islands more effectively than non-wooded green spaces. However, understanding of spatial configurations (variation in patch size and frequency) of forests across the gradient of urbanisation and between cities is limited to case studies. This represents a considerable knowledge gap for identification of general patterns that can inform integration of forest resources in UGI planning that have value beyond the individual city level. In this study we used Geographic Information Systems to explore the spatial configuration of forests across cities located within landscapes characterised by different levels of anthropogenic modification (degree of forest cover) and socio-political contexts, i.e. all Danish and Swedish cities >10,000 inhabitants (n = 176). We applied general linear modelling to investigate the relationship between forest cover, patch size and frequency with 1) regional landscape type, 2) demographic trends 1960–2010, and 3) the gradient of urbanisation (measured in three zones: urban core (0.2 km from city boundary), urban fringe (0.2–2 km), and urban periphery (2–5 km)). Regardless of demographic trends, forest cover was lowest in cities settled in large-scale agricultural regions, higher in regions with mosaics of forest and farming, and highest in forest-dominated regions. However, in all cities forest cover was lowest in the urban zone and peaked on the urban fringe rather than on the urban periphery. Furthermore, pocket woods (0.5–2 ha) accounted for over 50 % of patches in all three urban zones, irrespective of regional landscape type. We conclude by discussing how these general patterns could inform strategies for integration of urban forests in UGI planning.  相似文献   
32.
Free social spaces have long been emphasized in the social movement literature. Under names such as safe spaces, social havens, and counterpublics, they have been characterized as protective shelters against prevailing hegemonic ideologies and as hubs for the diffusion of ideas and ideologies. However, the vast literature on these spaces has predominantly focused on internal dynamics and processes, thus neglecting how they relate to the diffusion of collective mobilization. Inspired by formal modeling in collective action research, we develop a network model to investigate how the structural properties of free social spaces impact the diffusion of collective mobilization. Our results show that the assumption of clustering is enough for structural effects to emerge, and that clustering furthermore interacts synergistically with political deviance. This indicates that it is not only internal dynamics that play a role in the relevance of free social spaces for collective action. Our approach also illustrates how formal modeling can deepen our understanding of diffusion processes in collective mobilizations through analysis of emergent structural effects.  相似文献   
33.
This study analyses the outcomes of African independent power projects (IPPs). Nearly 40 such projects have taken root to date, concentrated mainly in 8 countries. More balanced outcomes are perceived in North Africa than across sub‐Saharan Africa (SSA), for reasons linked to more attractive investment environments, more robust policy frameworks, fewer planning mishaps, abundant low‐cost fuel and secure fuel contracts as well as credit enhancements such as sovereign guarantees. With few exceptions, these elements were absent in SSA, where the role of development finance institutions and the strategic management of projects seem more important.  相似文献   
34.
Abstract

Addressing the intersection of two important emerging research areas, re-distributed manufacturing (RDM) and the food-energy-water (FEW) nexus, this work combines insights from engineering, business and policy perspectives and explores opportunities and challenges towards a more localized and sustainable food system. Analysis centred on two specific food products, namely bread and tomato paste reveals that the feasibility and potential of RDM vary with the type of food product and the supply chain (SC) components. Physically, energy efficiency, water consumption and reduction of waste and carbon footprint may be affected by scale and location of production activities and potentials of industrial symbiosis. From the business perspective, novel products, new markets and new business models are expected in order for food RDM to penetrate within the established food industry. Studies on policies, through the lens of public procurement, call for solid evidence of envisioned environmental, social and economic benefits of a more localized food system. An initial integrated framework is proposed for understanding and assessing food RDM and the FEW nexus.  相似文献   
35.
This article provides a data‐driven assessment of economic and environmental aspects of remanufacturing for product + service firms. A critical component of such an assessment is the issue of demand cannibalization. We therefore present an analytical model and a behavioral study which together incorporate demand cannibalization from multiple customer segments across the firm's product line. We then perform a series of numerical simulations with realistic problem parameters obtained from both the literature and discussions with industry executives. Our findings show that remanufacturing frequently aligns firms' economic and environmental goals by increasing profits and decreasing the total environmental impact. We show that in some cases, an introduction of a remanufactured product leads to no changes in the new products' prices (positioning within the product line), implying a positive demand cannibalization and a decrease in the environmental impact; this provides support for a heuristic approach commonly used in practice. Yet in other cases, the firm can increase profits by decreasing the new product's prices and increasing sales—a negative effective cannibalization. With negative cannibalization the firm's total environmental impact often increases due to the growth in new production. However, we illustrate that this growth is nearly always sustainable, as the relative environmental impacts per unit and per dollar rarely increase.  相似文献   
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The article explores the context of the Estonian law on cultural autonomy from February 1925. It argues that the Jewish minority was an unintended beneficiary of the concession granted by the Estonian government to the Baltic Germans whose land ownership had been previously revoked. Unlike the ethnic Germans, who considered cultural autonomy a tactical retreat, the Jews took full advantage of the opportunity to strengthen communal bonds. Cultural autonomy was upheld throughout the 1930s mainly due to the strenuous desire of the authoritarian regime that ceased power in Estonia in 1934 to avoid a conflict with Nazi Germany. As for the Jews, the lack of irredentist tendencies ensured that they could preserve their status.  相似文献   
39.
We present a new mortality projection methodology that distinguishes smoking- and non-smoking-related mortality and takes into account mortality trends of the opposite sex and in other countries. We evaluate to what extent future projections of life expectancy at birth (e 0) for the Netherlands up to 2040 are affected by the application of these components. All-cause mortality and non-smoking-related mortality for the years 1970–2006 are projected by the Lee-Carter and Li-Lee methodologies. Smoking-related mortality is projected according to assumptions on future smoking-attributable mortality. Projecting all-cause mortality in the Netherlands, using the Lee-Carter model, leads to high gains in e 0 (4.1 for males; 4.4 for females) and divergence between the sexes. Coherent projections, which include the mortality experience of the other 21 sex- and country-specific populations, result in much higher gains for males (6.4) and females (5.7), and convergence. The separate projection of smoking and non-smoking-related mortality produces a steady increase in e 0 for males (4.8) and a nonlinear trend for females, with lower gains in e 0 in the short run, resulting in temporary sex convergence. The latter effect is also found in coherent projections. Our methodology provides more robust projections, especially thanks to the distinction between smoking- and non-smoking-related mortality.  相似文献   
40.
We study several important aspects of using environmental taxes to motivate the choice of innovative and “green" emissions‐reducing technologies as well as the role of fixed cost subsidies and consumer rebates in this process. In our model, a profit‐maximizing monopolistic firm facing price‐dependent demand selects emissions control technology, production quantity, and price in response to the tax, subsidy, and rebate levels set by the regulator. The available technologies vary in environmental efficiency as well as in the fixed and variable costs. Both the optimal policy for the firm and the social‐welfare maximizing policy for the regulator are analyzed. We find that the firm's reaction to an increase in taxes may be non‐monotone: while an initial increase in taxes may motivate a switch to a greener technology, further tax increases may motivate a reverse switch. For the regulator, we compare the social welfare achievable in the centralized system (which serves as an upper bound) to the highest level achievable under different classes of environmental policies. If the regulator is limited to a tax‐only policy, then when the regulator is moderately concerned with environmental impacts, the tax level that maximizes social welfare simultaneously motivates the choice of clean technology and closes the gap to the upper bound; however, both low and high levels of societal environmental concerns may lead to the choice of dirty technology and significant welfare losses as compared to the centralized case. Supplementing the environmental taxation with fixed cost subsidies and consumer rebates can eliminate this effect, expanding the range of parameters over which the green technology is chosen and often closing the welfare gap to the centralized solution.  相似文献   
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