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1.
National Park of Tijuca in Rio de Janeiro (Brazil) is about 3,300 ha and considered the largest urban forest in the world. Its floristic composition is typical of Atlantic Rain Forest. The reserve is being altered because of fire occurrences and urban expansion. This study identified locations and causes of forest fires, and makes management recommendations to restore damaged areas. From 1991 to 2000, forest firefighters recorded an average of 75-fire occurrences/year. Identified causes included hot air balloons (24%), intentional (24%), rubbish burning (21%) and religious practices (17%). Primary fuels included invasive grasses and ferns. Although hot air balloons destroyed larger areas of forest in each occurrence, a greater number of fires started in the invasive vegetation along roads that bisect the forest. In response to recurrent forests, invasive vegetation has spread gradually into the forest increasing forest degradation. To decrease fire damage, sites with high fire frequencies and density of invasive vegetation were planted with less flammable species. Results indicate that fire frequency decreased and density of invasive vegetation declined. This approach appears to prevent fire incidence, reduce the need for fire fighting, and preserve existing biodiversity.  相似文献   
2.
The model of development that has governed the modernization of farming in France is increasingly coming under attack. Given this, analysing the “work” that farming performs to “translate” the criticisms with which it must cope in formulating new definitions of roles is important in order to understand changes under way in this sector. The changes undergone by farming over the past eighty years are briefly presented and then the procedures and results of a survey, conducted during the mad cow disease among beef-farmers in Burgundy, are described. Light is thus shed on the diversity of the positions that farmers have adopted with regard to the future of their occupation. An interpretation is proposed of how the distribution (and interplay between) these positions might affect agriculture. - Special issue on Agriculture and food.  相似文献   
3.
We analyse whether the psychological pricing in the private sector has a public sector counterpart in tax policy. Analysing the main theoretical arguments for the existence of price points, and applying them to the public sector, suggests that psychological taxing reveals itself by the use of non-0 ending tax rates. The tax rate endings of the local income taxes, which are set by 308 Flemish municipalities in the fiscal year 1998, suggests the presence of psychological taxing. Non-0 endings occur more frequently in municipalities where demand for public policy is more elastic (and where, therefore, the benefits to the politicians from setting a tax just below a tax point is higher). The pre-tax income inequality and the level of the tax rate positively affect psychological taxing. The latter effect is reinforced in those municipalities where the existing tax rate is above the average tax rate in neighbouring municipalities and below their neighbours’ minimum, although this effect has a limited effect and is offset the further below the minimum the tax is set.  相似文献   
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This paper presents comparative results on poverty in seven countries and regions of the European Community: Belgium, The Netherlands, Luxembourg, Lorraine, Ireland, Catalonia and Greece. The data are obtained from comparable socio-economic surveys in each country. Subjective as well as relative poverty lines are used. The results indicate that the subjective poverty lines are plausible in a comparative context, although the levels of the subjective standards are rather generous. The estimated equivalence scales are much flatter than the one recommended by the OECD. The extent of poverty is much greater in the peripheral EC-countries than in the central ones. Though similar factors are found to be associated with poverty in all countries, there are also important differences in the characteristics of the poor across countries. The impact of social security transfers on poverty appears to be much smaller in the southern countries Greece and Catalonia, than in the Benelux and Lorraine.  相似文献   
7.
Risk Modeling, Assessment, and Management of Lahar Flow Threat   总被引:1,自引:0,他引:1  
The 1991 eruption of Mount Pinatubo in the Philippines is considered one of the most violent and destructive volcanic activities in the 20th century. Lahar is the Indonesian term for volcanic ash, and lahar flows resulting from the massive amount of volcanic materials deposited on the mountain's slope posed continued post-eruption threats to the surrounding areas, destroying lives, homes, agricultural products, and infrastructures. Risks of lahar flows were identified immediately after the eruption, with scientific data provided by the Philippine Institute of Volcanology, the U.S. Geological Survey, and other research institutions. However, competing political, economic, and social agendas subordinated the importance of scientific information to policy making. Using systemic risk analysis and management, this article addresses the issues of multiple objectives and the effective integration of scientific techniques into the decision-making process. It provides a modeling framework for identifying, prioritizing, and evaluating policies for managing risk. The major considerations are: (1) applying a holistic approach to risk analysis through hierarchical holographic modeling, (2) applying statistical methods to gain insight into the problem of uncertainty in risk assessment, (3) using multiobjective trade-off analysis to address the issue of multiple decisionmakers and stakeholders in the decision-making process, (4) using the conditional expected value of extreme events to complement and supplement the expected value in quantifying risk, and (5) assessing the impacts of multistage decisions. Numerical examples based on ex post data are formulated to illustrate applications to various problems. The resulting framework from this study can serve as a general baseline model for assessing and managing risks of natural disasters, which the Philippines' lead agency-the National Disaster Coordinating Council (NDCC)-and other related organizations can use for their decision-making processes.  相似文献   
8.
The current U.S. climate of racial and social injustice has prompted a renewed call for diverse and equitable ways to rethink community philanthropy. Community foundations are vehicles for community philanthropy which offer vast benefits for social improvement and community development. The board of directors ensures these organizations fulfill their mission, making decisions on funding priorities and holding the organization functionally and fiscally responsible. Drawing on constructs of diversity and representative bureaucracy and a case study of Florida community foundations, we suggest that diversity is understood in different ways and the presence of diverse board members may be linked to advancing the interests of diverse communities and in achieving outcomes that assist in the needs of certain social groups. Increased understanding of diversity can improve foundation and philanthropic effectiveness and bring broader social change by promoting equity and social justice among community‐based philanthropic organizations.  相似文献   
9.
New mothers frequently seek information and community on social networking sites as they seek to establish their parenting practices. As social networking sites for mothers (SNSM) present an environmental influence on the family system, a mother’s experience with social comparison, belonging, and emotion on SNSM can bear significant influence over her satisfaction with her parenting. The present study utilized survey methods to explore mothers’ (n= 336) reported experiences of these variables. We use structural equation modeling to specify a model with good fit, which indicated that greater downward comparison directly related to greater parenting satisfaction, with belonging and negative emotion as mediating indirect relationships. Implications for family communication and mothers’ SNSM practices are discussed.  相似文献   
10.
The objective of this article is to discuss a needed paradigm shift in disaster risk analysis to emphasize the role of the workforce in managing the recovery of interdependent infrastructure and economic systems. Much of the work that has been done on disaster risk analysis has focused primarily on preparedness and recovery strategies for disrupted infrastructure systems. The reliability of systems such as transportation, electric power, and telecommunications is crucial in sustaining business processes, supply chains, and regional livelihoods, as well as ensuring the availability of vital services in the aftermath of disasters. There has been a growing momentum in recognizing workforce criticality in the aftermath of disasters; nevertheless, significant gaps still remain in modeling, assessing, and managing workforce disruptions and their associated ripple effects to other interdependent systems. The workforce plays a pivotal role in ensuring that a disrupted region continues to function and subsequently recover from the adverse effects of disasters. With this in mind, this article presents a review of recent studies that have underscored the criticality of workforce sectors in formulating synergistic preparedness and recovery policies for interdependent infrastructure and regional economic systems.  相似文献   
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