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1.
Dennis Wagenaar Tiaravanni Hermawan Marc J. C. van den Homberg Jeroen C. J. H. Aerts Heidi Kreibich Hans de Moel Laurens M. Bouwer 《Risk analysis》2021,41(1):37-55
Damage models for natural hazards are used for decision making on reducing and transferring risk. The damage estimates from these models depend on many variables and their complex sometimes nonlinear relationships with the damage. In recent years, data‐driven modeling techniques have been used to capture those relationships. The available data to build such models are often limited. Therefore, in practice it is usually necessary to transfer models to a different context. In this article, we show that this implies the samples used to build the model are often not fully representative for the situation where they need to be applied on, which leads to a “sample selection bias.” In this article, we enhance data‐driven damage models by applying methods, not previously applied to damage modeling, to correct for this bias before the machine learning (ML) models are trained. We demonstrate this with case studies on flooding in Europe, and typhoon wind damage in the Philippines. Two sample selection bias correction methods from the ML literature are applied and one of these methods is also adjusted to our problem. These three methods are combined with stochastic generation of synthetic damage data. We demonstrate that for both case studies, the sample selection bias correction techniques reduce model errors, especially for the mean bias error this reduction can be larger than 30%. The novel combination with stochastic data generation seems to enhance these techniques. This shows that sample selection bias correction methods are beneficial for damage model transfer. 相似文献
2.
de Jong Petra W. Caarls Kim de Valk Helga A. G. 《Population research and policy review》2022,41(2):671-694
Population Research and Policy Review - The welfare state can be perceived as a safety net which helps individuals adjust to situations of risk or transition. Starting from this idea of the welfare... 相似文献
3.
Sant’Anna Annibal Parracho de Freitas Siqueira Sadok Menna Barreto Márcia 《Social indicators research》2020,148(3):733-746
Social Indicators Research - This paper analyses the Human Development Index (HDI) time series from 2010 to 2017. An alternative index is studied, which combines the same components of the HDI by... 相似文献
4.
From the inception of the proportional representation movement it has been an issue whether larger parties are favored at
the expense of smaller parties in one apportionment of seats as compared to another apportionment. A number of methods have
been proposed and are used in countries with a proportional representation system. These apportionment methods exhibit a regularity
of order, as discussed in the present paper, that captures the preferential treatment of larger versus smaller parties. This
order, namely majorization, permits the comparison of seat allocations in two apportionments. For divisor methods, we show
that one method is majorized by another method if and only if their signpost ratios are increasing. This criterion is satisfied
for the divisor methods with power-mean rounding, and for the divisor methods with stationary rounding. Majorization places
the five traditional apportionment methods in the order as they are known to favor larger parties over smaller parties: Adams,
Dean, Hill, Webster, and Jefferson.
Received: 5 August 2000/Accepted: 24 October 2001 相似文献
5.
Nairobi ME Network African Evaluation Association Secretariat Rseau Nigrian de Suivi et Evaluation Cape Verde Evaluation Network Rseau Malagache de Suivi et Evaluation Comoros Evaluation Network Eritrean Evaluation Network Malawi ME Network Rseau National de Chercheurs et Evaluateurs de Burundi Rwanda Evaluation Network UNICEF Eastern Southern Africa Region ME Network 《Evaluation and program planning》2002,25(4)
A review of the US ‘program evaluation standards’ (PES), undertaken in a series of workshops and meetings of networks of evaluators in Africa, resulted in modifications to those standards. The result was presented to a plenary session of the Inaugural Conference of the African Evaluation Association in September 1999, attended by over 300 evaluators from 35 countries. The AfrEA Conference decided that a systematic effort should be made to produce a list of African evaluation guidelines, similar to the PES, and that this checklist should be reviewed by national evaluation associations and networks in Africa and field tested in several countries. Ten national and regional networks and associations suggested modifications to the text and endorsed the final version of the guidelines. 相似文献
6.
Fire and restoration of the largest urban forest of the world in Rio de Janeiro City,Brazil 总被引:1,自引:1,他引:0
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
7.
8.
Albert A. Bartlett 《Population and environment》1993,14(4):359-387
This is a tutorial on the relations between population data and the rates of growth that are calculated from the data. For the calculation of rates of growth, discrete and continuous compounding will be compared so that the reader can see the reasons for using the mathematics of continuous compounding, which is the mathematics of exponential growth. Some properties of exponential growth are developed. Semi-logarithmic graphs will be discussed as a device for representing the size of growing populations and for analyzing the nature of the growth. Illustrative examples will be worked out in order to emphasize applications and utility. 相似文献
9.
ChrisdeWet 《河海大学学报(哲学社会科学版)》2002,4(2):16-20
论文在讨论四个移民典型案例的基础上 ,讨论在项目中与政策相关的教训 相似文献
10.
Two habituation experiments were conducted to investigate how 4‐month‐old infants perceive partly occluded shapes. In the first experiment, we presented a simple, partly occluded shape to the infants until habituation was reached. Then we showed either a probable completion (one that would be predicted on the basis of both local and global cues) or an improbable completion. Longer looking times were found for the improbably completed shape (compared to probable and control conditions), suggesting that the probable shape was perceived during partial occlusion. In the second experiment, infants were habituated to more ambiguous partly occluded shapes, where local and global cues would result in different completions. For adults, the percept of these shapes is usually dominated by global influences. However, after habituation the infants looked longer at the globally completed shapes. These results suggest that by the age of 4 months, infants are able to infer the perceptual completion of partly occluded shapes, but for more ambiguous shapes, this completion seems to be dominated by local influences. 相似文献