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91.
Security of Big Data is a huge concern. In a broad sense, Big Data contains two types of data: structured and unstructured. Providing security to unstructured data is more difficult than providing security to structured data. In this paper, we have developed an approach to provide adequate security to unstructured data by considering types of data and their sensitivity levels. We have reviewed the different analytics methods of Big Data to build nodes of different types of data. Each type of data has been classified to provide adequate security and enhance the overhead of the security system. To provide security to a data node, and a security suite has been designed by incorporating different security algorithms. Those security algorithms collectively form a security suite which has been interfaced with the data node. Information on data sensitivity has been collected through a survey. We have shown through several experiments on multiple computer systems with varied configurations that data classification with respect to sensitivity levels enhances the performance of the system. The experimental results show how and in what amount the designed security suite reduces overhead and increases security simultaneously.  相似文献   
92.
Understanding the economic integration of minority ethnic communities requires an analysis of the educational process. This paper examines second‐generation immigrant youths’ educational attainments in comparison with those of similarly aged native Swedes. Binomial‐logit, grouped‐regression and multinomial‐logit models are applied to longitudinal data, 1991–1996. The results give evidence for socioeconomic determinants of post‐compulsory education and for parental influence on educational choices. Parental income affects second‐generation immigrants’ post‐compulsory education and Swedes’ choice of level of education. In general, the stronger the labour market positions of the parents, the higher the probability of the children continuing education. It is also found that the geographical origin of second‐generation immigrants matter, with youths of Asian origin having a higher probability of continuing their education. We suggest policy changes on different levels based on the evidence of the paper, as short‐run, long‐run and in general.  相似文献   
93.
94.
While univariate nonparametric estimation methods have been developed for estimating returns in mean-downside risk portfolio optimization, the problem of handling possible cross-correlations in a vector of asset returns has not been addressed in portfolio selection. We present a novel multivariate nonparametric portfolio optimization procedure using kernel-based estimators of the conditional mean and the conditional median. The method accounts for the covariance structure information from the full set of returns. We also provide two computational algorithms to implement the estimators. Via the analysis of 24 French stock market returns, we evaluate the in-sample and out-of-sample performance of both portfolio selection algorithms against optimal portfolios selected by classical and univariate nonparametric methods for three highly different time periods and different levels of expected return. By allowing for cross-correlations among returns, our results suggest that the proposed multivariate nonparametric method is a useful extension of standard univariate nonparametric portfolio selection approaches.  相似文献   
95.
In this paper, we show that the 1986 Mitra–Wan result establishing asymptotic convergence of maximal programs to the unique golden-rule forest in the case of undiscounted, strictly concave felicity functions can be strengthened, in the same setting, to the  uniform  asymptotic convergence of  optimal  programs to the unique golden-rule forest. We work with a notationally reformulated version of the model that may have independent interest.  相似文献   
96.
Common perceptions about broad-based black economic empowerment (BBBEE) have been that it is nothing more than a tool for the already affluent to access further wealth and has limited potential to address the economic exclusion of the most marginalised. An analysis was conducted of data on black economic empowerment (BEE) deals between 2004 and 2009. The findings demonstrate that although the elite continue to benefit from deals, broad-based beneficiaries, particularly employees and women, are also beginning to benefit to some extent. This suggests that empowerment policies have some potential to promote private sector involvement in addressing the state's social transformation agenda. However, a closer analysis of the BEE transactions shows that the BEE landscape is far more complex and nuanced than commonly thought. Further research is necessary to understand the real impacts of BEE on the ground.  相似文献   
97.
This article analyses how a crisis impacts labour markets in origin countries through migration channels. For this purpose, we develop a novel dynamic general equilibrium model with a focus on the interlinkages between migration, the labour market and education. The main innovation of the paper is the retrospective modelling in general equilibrium of the impact of an economic crisis to isolate the impact of migration on local unemployment. The impact of the crisis on education decision is captured through endogenous returns to education. The simultaneity of the crisis in Tunisia and its partners worsened the labour market situation mainly through the increase in labour supply. The main result of this study is that migration is indeed one of the main determinants of the unemployment increase and that remittances have a higher impact than the variation of emigration flows. The low skilled bear the highest costs in terms of unemployment and wage decline.  相似文献   
98.
This case study of tanneries in Kasur presents an account of industrial transformation of an agrarian society in a developing country, Pakistan, with its effects, efforts to rehabilitate and the difficulties faced in abatement of pollution. The research attempts to respond to the question of the social and economic cost of achieving pollution abatement in Kasur and develop a viable model. The research methods adopted include reviews of secondary data, personal interview and sample survey of tanneries in the study area. The results reveal how people have grappled with the problem of pollution abatement from the tanneries in Kasur and in creating decisive awareness at the local, national and international levels. The transformation of the city from a commercial centre to a semi-industrial tanning centre has led to a loss of 30% cultivable area due to contamination. It is reported that crop yield has dropped by 50% over the past 10 years. The total loss of agricultural income is estimated to be $450 thousand US per annum. The environmental impact of tanneries is highly pronounced in the urban areas around the leather tanning industrial units. Strong protest by the affected population has to some extent forced industrialists to rehabilitate the environment. NGO and the Government are also contributing to this effort. The case study of Kasur presents an example of the community's efforts to mobilize its local, financial and political resources to overcome the environmental hazards, with the associated problems and dilemmas.  相似文献   
99.
Work on the impact of U.S. monetary policy on emerging financial markets mostly focuses on official target rate announcements; empirical evidence using data on informal communication channels, such as speeches, is scant. Employing a unique data set covering formal and informal communication channels in a generalized autoregressive conditional heteroskedasticity model framework, we provide comprehensive evidence on the effects of U.S. monetary policy on 17 emerging equity market returns over the period 1998–2009. We find, first, that both monetary policy actions and communications have a significant impact on market returns. Second, target rate change surprises are an important driver of emerging market returns. However, informal communications—particularly when taking into account their higher frequency—have a larger (cumulative) influence on returns than do target rate surprises. Third, during the recent financial crisis, central bank communication played an even more pronounced role. Finally, American emerging markets react more to communications than do non‐American markets.  相似文献   
100.
Explosions in hydrogen chloride storage tanks are very rare. However, we have experienced one. The explosion was so powerful that the tank with a capacity 250 kL, 60% filled with 33% HCL, took off from the ground went up to 8–9 m high in air and landed around 50 m away. The contents of the tank sprayed all over the nearby area. Though the tank was surrounded by other plants and equipment, fortunately, it landed in a barren area. This averted loss of life and property that would have otherwise resulted. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009  相似文献   
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