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41.
In the last decades, large amount of effort and resources have been spent in projects and programs aiming to develop rural communities. The ultimate goal of such projects is supposed to be the improvement of the Quality of Life (QOL) of these communities. Although improving the Quality of the Living Conditions (QLC) is an acceptable strategy to reach that goal, all too often there is significant confusion between the two concepts. In this paper we argue that QLC and QOL can not be dissociated, but they are distinct. Our hypothesis is that we can make this distinction objectively. For that purpose, we develop an Index of the Quality of Living Conditions (IQLC) and an Index of the Quality of Life (IQOL). Each index is obtained by combining partial indicators of the conditions of several aspects in several dimensions (e.g., social, environmental, and economic). While the assessment of living conditions to obtain the IQLC is done by project staff, the IQOL is based on the manifestation of the farmers about their satisfaction in living those conditions. The IQLC and the IQOL result, then, from different views of the same aspects of life in a given context. Therefore, their objective measurement can be a useful instrument to evaluate the effectiveness of improvements on living conditions proposed by institutions and their professionals to improve the quality of life of rural communities.  相似文献   
42.
The Brazilian Amazon is an area of both serious environmental degradation and social instability. Despite billions of dollars spent on economic development and the rapid pace of urbanization, deforestation is extreme and violent land conflict is intense. Although episodes of conflict over land are common in Brazilian history, this paper focuses on agrarian issues that arose with the opening of the Amazon frontier in the 1970s. The paper argues that the nature of land conflict in the eastern Brazilian Amazon is dynamic, and proposes a two-stage model to illustrate how the struggle has evolved from an agrarian phenomenon to an organized resistance that is urban-based. Recognizing the interaction between cities and rural areas in the frontier reaches of the Brazilian Amazon is key to understanding the land struggle in the face of urbanization. The analytical framework deployed considers the transformation of the region from an agrarian frontier to an urbanized frontier, assessing the dynamic nature of the land struggle and examining the implications for land cover change.  相似文献   
43.
ABSTRACT

Many financial decisions such as portfolio allocation, risk management, option pricing and hedge strategies are based on the forecast of the conditional variances, covariances and correlations of financial returns. Although the decisions depend on the forecasts covariance matrix little is known about effects of outliers on the uncertainty associated with these forecasts. In this paper we analyse these effects on the context of dynamic conditional correlation models when the uncertainty is measured using bootstrap methods. We also propose a bootstrap procedure to obtain forecast densities for return, volatilities, conditional correlation and Value-at-Risk that is robust to outliers. The results are illustrated with simulated and real data.  相似文献   
44.
45.
This paper presents one Post-Occupancy Evaluation (POE) done in a child care institution in the city of Florianópolis, in south of Brazil. The objective of this work is to analyze the environment's performance of the child care center considering the well-being of all of its users, with the mainly focus in the teacher's work. For this analyze, was used a multi methods approach, using consecrated evaluations in the area of environmental psychology and ergonomic. The methods used were: Exploratory Visit, Walkthrough, Questionnaires, Observations, Ergonomic Analyze and Poem of Wishes. The methodological procedures used enabled the identification of the main problems that committed the interaction between environment, user and task, which in addition to serve as an argument to the recommendations done to the analyzed Institution, form a repertory that can serve as a base to future projects in institutions with the same character.  相似文献   
46.
Recent cross-country growth studies have found that ethnolinguistic fractionalization is an important explanatory variable of long-run growth performance. This paper highlights some limitations of cross-country studies by focusing on the time series evidence for South Africa. In presenting variation over time in a number of social dimensions, this paper adds longitudinal evidence on a range of dimensions that have been linked to long run economic development. Given South Africa’s history of ethnic and racial politics, it constitutes a useful case study to explore the dynamics of the possible effects of ethnolinguistic fractionalization on growth. We introduce several new sets of fractionalization indicators for South Africa: ethnolinguistic, religious and cultural fractionalization, and a polarization measure. The results of this study provide important nuance to the existing body of evidence, for the use of fractionalization indices in growth studies.
Raphael de KadtEmail:
  相似文献   
47.
The cultivation of sugar cane has been gaining great focus in several countries due to its diversity of use. The modernization of agriculture has allowed high productivity, which is affected by the invasion of weeds. With sustainable agriculture, the use of herbicides has been increasingly avoided in society, requiring more effective weed control methods. In this paper, we propose a statistical model capable of identifying the invasion of weeds in the field, using four color spectra as regressor variables obtained by a multispectral camera mounted on an unmanned aerial vehicle. With the exact identification of the weed infestation, it is possible to carry out the management in the field with herbicide applications in the exact places, thus avoiding the increase of the cost of production or even dispensing with the use of herbicides, effecting the mechanical removal of them. Results show that in the experimental field, it was possible to reduce herbicide spraying by 57%.  相似文献   
48.
This paper proposes a column generation approach for the Point-Feature Cartographic Label Placement problem (PFCLP). The column generation is based on a Lagrangean relaxation with clusters proposed for problems modeled by conflict graphs. The PFCLP can be represented by a conflict graph where vertices are positions for each label and edges are potential overlaps between labels (vertices). The conflict graph is decomposed into clusters forming a block diagonal matrix with coupling constraints that is known as a restricted master problem (RMP) in a Dantzig-Wolfe decomposition context. The clusters’ sub-problems are similar to the PFCLP and are used to generate new improved columns to RMP. This approach was tested on PFCLP instances presented in the literature providing in reasonable times better solutions than all those known and determining optimal solutions for some difficult large-scale instances.  相似文献   
49.
ABSTRACT

We propose a new semiparametric Weibull cure rate model for fitting nonlinear effects of explanatory variables on the mean, scale and cure rate parameters. The regression model is based on the generalized additive models for location, scale and shape, for which any or all distribution parameters can be modeled as parametric linear and/or nonparametric smooth functions of explanatory variables. We present methods to select additive terms, model estimation and validation, where all computational codes are presented in a simple way such that any R user can fit the new model. Biases of the parameter estimates caused by models specified erroneously are investigated through Monte Carlo simulations. We illustrate the usefulness of the new model by means of two applications to real data. We provide computational codes to fit the new regression model in the R software.  相似文献   
50.
This paper refers to the development of a signage system, driven by the vector of Signage Design and Informational Ergonomics associated with Regulatory Standards. The methodology of the Ergonomic Intervention of Moraes and Mont'Alv?o (2003), in its early stages, and the Method of the Signage Pyramid of Calori (2007) were used to develop the research, data collection and analysis and to guide the design by a signaling system. The system contemplated by this job is called Mount Zion, a site of 19 hectares, which has signs of disturbance. As a result, we obtained a signaling system, with graphic features that refer to formal-site, capable of meeting the needs of orientation and displacement inherent to the site.  相似文献   
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