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21.
In 2015, the United Nations (UN) issued probabilistic population projections for all countries up to 2100, by simulating future levels of total fertility and life expectancy and combining the results using a standard cohort component projection method. For the 40 countries with generalized HIV/AIDS epidemics, the mortality projections used the Spectrum/Estimation and Projection Package (EPP) model, a complex, multistate model designed for short-term projections of policy-relevant quantities for the epidemic. We propose a simpler approach that is more compatible with existing UN projection methods for other countries. Changes in life expectancy are projected probabilistically using a simple time series regression and then converted to age- and sex-specific mortality rates using model life tables designed for countries with HIV/AIDS epidemics. These are then input to the cohort component method, as for other countries. The method performed well in an out-of-sample cross-validation experiment. It gives similar short-run projections to Spectrum/EPP, while being simpler and avoiding multistate modelling.  相似文献   
22.
隐喻是构成诗歌体裁特征的重要要素,许多重要诗论也论证过诗性隐喻对于提高认知能力和反映认知现象的重要意义。概念隐喻认为隐喻是一种认知手段,是理解世界、产生意义的重要途径。其本质是概念性的,是跨概念域的系统映射。雪莱的《给——温柔的歌声已消逝》通过对歌声和音乐、芳香和紫罗兰等具体概念的描述,映射到与思维情感相关的抽象概念上,生动地传达出了留恋逝去爱情的强烈感受,为无形的爱情穿上了一件有形的外衣。运用概念隐喻理论对该诗歌进行分析,不仅能够给予理解这首诗歌一个更加新颖的视角,更能对隐喻传达抽象情感有更加具体的认识。  相似文献   
23.
This paper presents a general method of constructing schematic saturated orthogonal arrays of strength two. We consider a class of mixed saturated orthogonal arrays produced from saturated symmetric orthogonal arrays by using the contractive replacement method, study the Hamming distances of the rows, construct their association schemes, and prove that they are schematic. Some examples are given to illustrate this construction method.  相似文献   
24.
The multiple non symmetric correspondence analysis (MNSCA) is a useful technique for analyzing a two-way contingency table. In more complex cases, the predictor variables are more than one. In this paper, the MNSCA, along with the decomposition of the Gray–Williams Tau index, in main effects and interaction term, is used to analyze a contingency table with two predictor categorical variables and an ordinal response variable. The Multiple-Tau index is a measure of association that contains both main effects and interaction term. The main effects represent the change in the response variables due to the change in the level/categories of the predictor variables, considering the effects of their addition, while the interaction effect represents the combined effect of predictor categorical variables on the ordinal response variable. Moreover, for ordinal scale variables, we propose a further decomposition in order to check the existence of power components by using Emerson's orthogonal polynomials.  相似文献   
25.
在回顾2014年国际原油市场主要发展历程的基础上,从两方面对2015年油价走势进行了发展态势展望和预测分析。研究认为:受全球经济形势复杂多变,复苏进程缓慢、脆弱而不均衡以及供需基本面因素的主要作用,在产量相对过剩情况下,2015年油价上半年依旧延续下跌趋势,国际原油价格还将在低位震荡,下半年或出现企稳反弹,全年油价波动幅度小于2014年。预计Brent原油均价为50~65美元/桶,WTI原油均价为45~60美元/桶。  相似文献   
26.
Following the release of the Intergenerational Report, the Australian Treasury identified the levers to address the economic effects of demographic ageing as ‘the three Ps’: population, participation and productivity. To date, the first ‘P’, population, has been treated as an exogenous factor, with the common view being that there is very little that the government can do to supplant demographic ageing. Focusing upon labour supply, this paper shows how variation in Australia’s underlying demography can significantly alter Australia’s future labour supply. Although governments cannot redirect the cohort flow component of population ageing, much can be achieved in promoting growth of the labour supply by maintaining or increasing fertility (in the longer term), or increasing targeted migration (in the short to medium term). This paper also decomposes the relative role of cohort flow, changing demography and changing labour force participation on the growth of the labour supply over the past 20 years. Over this period, the entry of the baby boom generation (cohort flow) and increased labour force participation of women accounted for almost all of the growth in the labour force. Changing demography had very little effect. However, Australias future labour supply will not include a large increase in cohort flow (as caused by the baby boomers) or a very large increase in female labour force participation. Regardless of the assumptions used, labour supply growth will be considerably lower in the next and subsequent 20 years, when compared to the previous 20.  相似文献   
27.
Compared to other countries that have suffered from the Nazioccupation, the destructive impact of the Holocaust on theJewish population has been particularly strong in the Netherlands. This paper gives a demographicreconstruction of the Jewish population in the Netherlands by the end of the war (1945),disaggregated by age and sex. The reconstruction is based on two approaches: a forwardprojection 1941–1945, starting from registration data supplemented by information onHolocaust losses; and a backward projection 1966–1945, starting from an enumerationof Halachic Jews carried out in 1966. The two approaches yieldtwo estimates that are comfortingly similar.  相似文献   
28.
概念整合网络与新闻漫画的语义构建   总被引:3,自引:0,他引:3  
文章首先回顾了认知语言学中Fauconnier和Tunner等人提出的概念整合理论的主要概念和基本思想,然后运用这一理论探讨了新闻漫画的语义构建,并选取三副网络新闻漫画进行了个案分析,旨在说明概念整合理论的认知解释力.分析表明,概念整合理论具有解释在线构建非传统意义上的新颖意义的特性,能够为新闻漫画的语义构建、创新和理解提供一个新的理论视角.  相似文献   
29.
In recent years, the issue of water allocation among competing users has been of great concern for many countries due to increasing water demand from population growth and economic development. In water management systems, the inherent uncertainties and their potential interactions pose a significant challenge for water managers to identify optimal water-allocation schemes in a complex and uncertain environment. This paper thus proposes a methodology that incorporates optimization techniques and statistical experimental designs within a general framework to address the issues of uncertainty and risk as well as their correlations in a systematic manner. A water resources management problem is used to demonstrate the applicability of the proposed methodology. The results indicate that interval solutions can be generated for the objective function and decision variables, and a number of decision alternatives can be obtained under different policy scenarios. The solutions with different risk levels of constraint violation can help quantify the relationship between the economic objective and the system risk, which is meaningful for supporting risk management. The experimental data obtained from the Taguchi's orthogonal array design are useful for identifying the significant factors affecting the means of total net benefits. Then the findings from the mixed-level factorial experiment can help reveal the latent interactions between those significant factors at different levels and their effects on the modeling response.  相似文献   
30.
二维奇异问题的有限元方法是实际中经常会遇到的一类问题,对其解决有重要意义.本文讨论二维奇异非稳态问题的有限元方法,证明了弱解的存在唯一性,并给出有限元解的加权L2-模估计.  相似文献   
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