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1.
This paper presents some of the findings derived from a UK Aimhigher South Yorkshire research report on disability and higher education. Many of the students who shared their life histories for this project found that there was a lack of information in making choices about their futures, especially information about pursuing higher education. Without information to make informed choices, disabled students not only experience stress and anxiety, but also difficulty in preparing themselves for higher education study. This is, perhaps, reason for the low proportion of disabled learners in further and higher education. There are many reasons to explain this disparity. Many factors are inextricably linked to disablism institutionalized within many sectors of education. The education arena is not being singled out here. However, it does serve as further notice of the pervasiveness of disablism existing in wider society.  相似文献   
2.
In this paper we develop a study on several types of parallel genetic algorithms (PGAs). Our motivation is to bring some uniformity to the proposal, comparison, and knowledge exchange among the traditionally opposite kinds of serial and parallel GAs. We comparatively analyze the properties of steady-state, generational, and cellular genetic algorithms. Afterwards, this study is extended to consider a distributed model consisting in a ring of GA islands. The analyzed features are the time complexity, selection pressure, schema processing rates, efficacy in finding an optimum, efficiency, speedup, and resistance to scalability. Besides that, we briefly discuss how the migration policy affects the search. Also, some of the search properties of cellular GAs are investigated. The selected benchmark is a representative subset of problems containing real world difficulties. We often conclude that parallel GAs are numerically better and faster than equivalent sequential GAs. Our aim is to shed some light on the advantages and drawbacks of various sequential and parallel GAs to help researchers using them in the very diverse application fields of the evolutionary computation.  相似文献   
3.
Recently, we developed a GIS-Integrated Integral Risk Index (IRI) to assess human health risks in areas with presence of environmental pollutants. Contaminants were previously ranked by applying a self-organizing map (SOM) to their characteristics of persistence, bioaccumulation, and toxicity in order to obtain the Hazard Index (HI). In the present study, the original IRI was substantially improved by allowing the entrance of probabilistic data. A neuroprobabilistic HI was developed by combining SOM and Monte Carlo analysis. In general terms, the deterministic and probabilistic HIs followed a similar pattern: polychlorinated biphenyls (PCBs) and light polycyclic aromatic hydrocarbons (PAHs) were the pollutants showing the highest and lowest values of HI, respectively. However, the bioaccumulation value of heavy metals notably increased after considering a probability density function to explain the bioaccumulation factor. To check its applicability, a case study was investigated. The probabilistic integral risk was calculated in the chemical/petrochemical industrial area of Tarragona (Catalonia, Spain), where an environmental program has been carried out since 2002. The risk change between 2002 and 2005 was evaluated on the basis of probabilistic data of the levels of various pollutants in soils. The results indicated that the risk of the chemicals under study did not follow a homogeneous tendency. However, the current levels of pollution do not mean a relevant source of health risks for the local population. Moreover, the neuroprobabilistic HI seems to be an adequate tool to be taken into account in risk assessment processes.  相似文献   
4.
Axiomatizations of the normalized Banzhaf value and the Shapley value   总被引:1,自引:1,他引:0  
A cooperative game with transferable utilities– or simply a TU-game – describes a situation in which players can obtain certain payoffs by cooperation. A solution concept for these games is a function which assigns to every such a game a distribution of payoffs over the players in the game. Famous solution concepts for TU-games are the Shapley value and the Banzhaf value. Both solution concepts have been axiomatized in various ways. An important difference between these two solution concepts is the fact that the Shapley value always distributes the payoff that can be obtained by the `grand coalition' consisting of all players cooperating together while the Banzhaf value does not satisfy this property, i.e., the Banzhaf value is not efficient. In this paper we consider the normalized Banzhaf value which distributes the payoff that can be obtained by the `grand coalition' proportional to the Banzhaf values of the players. This value does not satisfy certain axioms underlying the Banzhaf value. In this paper we introduce some new axioms that characterize the normalized Banzhaf value. We also provide an axiomatization of the Shapley value using similar axioms. Received: 10 April 1996 / Accepted: 2 June 1997  相似文献   
5.
Chile modernized its social model in two stages characterized by different strategies: developmentalism (1924–73) and the Washington Consensus (1973–2008). In the first stage, the State pursued both social policies of universal coverage and land reform, while also building up the country's economic and institutional infrastructure. After the 1973 military coup, some public services were dismantled and privatized, and the labour movement was suppressed. Since the end of the dictatorship in 1990, resistance to state regulation and an anti‐labour bias have persisted, albeit to a diminishing degree due to advances in democratization and, latterly, the current world economic crisis.  相似文献   
6.
It is well-known that under fairly conditions linear regression becomes a powerful statistical tool. In practice, however, some of these conditions are usually not satisfied and regression models become ill-posed, implying that the application of traditional estimation methods may lead to non-unique or highly unstable solutions. Addressing this issue, in this paper a new class of maximum entropy estimators suitable for dealing with ill-posed models, namely for the estimation of regression models with small samples sizes affected by collinearity and outliers, is introduced. The performance of the new estimators is illustrated through several simulation studies.  相似文献   
7.
We propose an influence diagnostic methodology for linear regression models with stochastic restrictions and errors following elliptically contoured distributions. We study how a perturbation may impact on the mixed estimation procedure of parameters in the model. Normal curvatures and slopes for assessing influence under usual schemes are derived, including perturbations of case-weight, response variable, and explanatory variable. Simulations are conducted to evaluate the performance of the proposed methodology. An example with real-world economy data is presented as an illustration.  相似文献   
8.
The establishment of the European Higher Education Area has involved specifying lists of professional competencies that programs are expected to develop, and with this the need for procedures to measure how every course within a higher education program is aligned with the program's competencies. We propose an instrument for characterizing this alignment, a process that we call assessing the relevance of a course. Using information from the course syllabus (objectives, contents and assessment scheme), our instrument produces indicators for characterizing the syllabus in terms of a competence list and for assessing its coherence. Because assessment involves quality, the results obtained can also be used to revise and improve the course syllabus. We illustrate this process with an example of a methods course from a mathematics teacher education program at a Spanish university.  相似文献   
9.
How Satisfied are Spouses with their Leisure Time? Evidence from Europe   总被引:1,自引:1,他引:0  
This paper first identifies the determinants of spouses’ satisfaction levels within the household with respect to their leisure time and, secondly, characterizes whether their preferences have some degree of altruistic or egoistic character in regard to this particular satisfaction. To that end, it formulates a theoretical framework from the collective family model whose stochastic formulations are estimated for 14 EU countries. The general empirical results first reveal that the presence of children has a significantly negative impact on the leisure satisfaction of both spouses. Then, increases in individual incomes lead to lower own leisure satisfaction levels. Both husbands and wives show egoistic behavior with respect to the labor and non-labor incomes (wage rate) of their respective spouses’ satisfaction levels.
María NavarroEmail:
  相似文献   
10.
Urban Ecosystems - Urban streams provide important ecosystem services to cities’ population, from the maintenance of urban biodiversity, temperature, humidity and air quality to improving...  相似文献   
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