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1.
Financial stress index (FSI) is considered to be an important risk management tool to quantify financial vulnerabilities. This paper proposes a new framework based on a hybrid classifier model that integrates rough set theory (RST), FSI, support vector regression (SVR) and a control chart to identify stressed periods. First, the RST method is applied to select variables. The outputs are used as input data for FSI–SVR computation. Empirical analysis is conducted based on monthly FSI of the Federal Reserve Bank of Saint Louis from January 1992 to June 2011. A comparison study is performed between FSI based on the principal component analysis and FSI–SVR. A control chart based on FSI–SVR and extreme value theory is proposed to identify the extremely stressed periods. Our approach identified different stressed periods including internet bubble, subprime crisis and actual financial stress episodes, along with the calmest periods, agreeing with those given by Federal Reserve System reports. 相似文献
2.
Open innovation and absorptive capacity are two concepts based on the idea that companies can leverage the knowledge generated externally to improve their innovation performance. The aim of this paper is to analyse the joint effect of open innovation and absorptive capacity on a firm's radical innovation. Open innovation is expressed in terms of external search breadth and depth strategies and absorptive capacity is described by distinguishing between potential and realized absorptive capacity. In order to test our hypotheses, we carried out empirical research in firms operating in high-technology industries. The results indicate that internal routines and processes for absorbing external knowledge help explain radical innovation as they show a significant effect of potential and realized absorptive capacity. Also, there is a moderating effect of absorptive capacity on open innovation. Specifically, potential absorptive capacity exerts a positive effect on the relationship between external search breadth and depth and radical innovation. Realized absorptive capacity moderates the influence of external search breadth. These findings confirm the complementary nature of absorptive capacity and open innovation search strategies on radical innovation. 相似文献
3.
Luis Villar-Fidalgo María del Mar Espinosa Escudero Manuel Domínguez Somonte 《生产规划与管理》2019,30(8):624-638
Not only ETO (Engineering to Order), but even serial production industry should know how to deal with projects and their schedule: plant commissioning, shutdown, introducing new products and similar circumstances should be managed with adequate planning and resource allocation techniques to create a schedule useful in decision making during the execution. The current complex reality, with evolving technologies and fierce pressure to reach the market as soon as possible, pushes the project managers to use more advanced techniques than waterfall planning, such as agile or lean. It also requires them to take a holistic view and manage concurrent tasks in complex projects. The contributions of this paper are two: the proposal to control specific parallel groups of waterfall activities under uncertain environments, which can lead to iterations and reworks, as a single concurrent Activity Managed by Kanban Methods (AMKM). This activity can be subsequently embedded into traditional scheduling approaches as CPM-PERT. The second contribution is the feasibility of its application in industrial environments due to the affordability of simulation software. Two use cases are shown as evidence. It is not a disruptive proposal, but a kaizen action based on very mature technologies. Finally, it is suggested some improvements to be implemented in Project Management Software due to this ‘kaizen’ proposal. 相似文献
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María del Carmen Méndez García 《Intercultural Education》2005,16(1):57-68
The sociocultural content of foreign language textbooks has become a concern of scholars and practitioners owing to the fact that the traditional emphasis on purely linguistic issues has been expanded to embrace a language in context approach. This paper studies the English‐speaking communities that are described in English language teaching textbooks marketed in Spain. It examines to what extent an international and/or intercultural approach is a constituent element in their design. 相似文献
7.
Demographic Shifts in the Czech Republic after 1989: A Second Demographic Transition View 总被引:1,自引:1,他引:0
A dramatic change in fertility,family formation and living arrangements tookplace in the Czech Republic over the 1990s. Theestablishment of democracy, profound socialtransformation and transition to the marketeconomy affected the values and demographicbehaviour of the young Czech generation. Thispaper examines whether these demographic shiftscan be interpreted within the framework of thesecond demographic transition. The theoreticalpart discusses the idea of the transition,outlining three distinctive conceptualisations.Two of them – the view of the transition as aprogression of characteristic interrelateddemographic changes and a broader viewstressing the importance of underlyingideational factors – fit the Czech situationvery well. A comparison with the Netherlandsreveals that the onset of the transition in theCzech Republic may be clearly located in thefirst half of the 1990s, lagging two decadesbehind the Netherlands. 相似文献
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This paper studies optimum designs for linear models when the errors are heteroscedastic. Sufficient conditions are given
in order to obtainD-, A- andE-optimum designs for a complete regression model from partial optimum designs for some sub-parameters. A result about optimality
for a complete model from the optimality for the submodels is included.
Supported by Junta de Andalucía, research group FQM244. 相似文献
10.
A comparative study conducted in the Sudan illustrated both the potential of a nutrition education program for pregnant women and the many obstacles to creating more optimal maternal nutrition. Included in the study were 1200 women 18-34 years of age attending the Khartoum Province Model Clinic for a minimum of 5 prenatal visits. 83.3% were Muslims and 48.2% were illiterate. The 60 women who comprised the experimental group were exposed to individual nutrition counseling and home visits. Overall, 70% of subjects were anemic, 27% had malaria, and 18% were hookworm. The average weight gain during pregnancy was 4.5 kgs; 25.0% of controls and 20.0% of those in the experimental group gained 3.5-4.0 kgs, 18.3% of controls and 33.3% of experimental subjects gained 4.5-5.0 kgs, and 23.3% of controls and 30.0% of those in the experimental groups gained 5.5 kgs or more. 53.0% of controls and 61.7% of women exposed to nutrition education breastfed for at least 6 months, and 70% of women in the former group and 95% of those in the latter had enrolled their infants in an immunization program. A baseline nutrition questionnaire revealed widespread misinformation, especially a belief that pregnant women should reduce their food intake from 3 to 1-2 meals per day to prevent the fetus from growing too large and making labor difficult. Foods such as fermented sorghum products, fresh fish, and water melon were regarded as abortifacients and avoided, while hot pepper, sour milk, and cola sodas were considered nutritious. Consumption was self-reported to be poor for milk products by 25% of mothers, for meat by 16%, and for fruits and vegetables by 40% Although the educational intervention increased women's knowledge of basic nutrition, it had only a minimal effect on actual practice. This finding is assumed to reflect the widespread belief that men and their guests should be given preference in food allocation, poverty, and avoidance, on the basis of tradition, of many healthy foods. Since 72% of women reported ownership of a television, use if this medium is recommended for nutrition education. 相似文献