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111.
现代信息服务业是国民经济和现代服务业的重要组成部分。加快现代信息服务业发展是经济社会转型升级的必然选择。文章在分析我国现代信息服务业发展现状及问题的基础上,探讨了经济社会转型升级需要现代信息服务业推动,并从科学制定发展规划、加强人才培育与引进、优化产业结构等方面提出了加快现代信息服务业发展的对策。  相似文献   
112.
针对多层微波集成电路设计的微带线层间互连问题,介绍了垂直通孔互连、垂直带条互连和层耦合过渡互连三种高性能的互连方法,并且采用三维电磁仿真软件HFSS对这三种互连结构进行了建模和仿真。仿真结果表明,垂直通孔互连和垂直带条互连在0.1~25 GHz的频宽范围内,回波损耗S11<-20 dB,插入损耗S21>-1 dB,互连性能优良,而层耦合过渡互连在20~68 GHz内回波损耗S11 <-20 dB,插入损耗S21>-1 dB,具有在毫米波频段实现互连的潜力。  相似文献   
113.
It is widely accepted that disparities in education contribute to the poor labour market outcomes experienced by ethnic minority groups and consequently to their poverty. In this article, I analyse differential educational benefits in Bulgaria and compare returns to education for the Roma minority with the majority population and the Turkish minority. I show that both ethnic minority groups have lower education levels and employment rates than the majority population and that they also have lower returns to education. This result could be related to minorities' lower education quality as well as to discrimination in the labour market. Integration policies should thus aim to improve employability and labour market competence of vulnerable groups starting from school.  相似文献   
114.
针对目前我国建筑材料的发展现状,论述了节约型社会发展新型节能建材的必要性,以及新型墙体材料、保温隔热材料、防水密封材料、装饰装修材料的发展现状及趋势,发展新型节能建筑材料对于落实科学发展观和构建资源节约型社会具有的重要现实意义。  相似文献   
115.
The westernization of Asian countries has led to the rapid expansion of Western-style fast-food restaurants, which are believed to be fueling an unprecedented rise in body mass in these countries. This study tests this belief using longitudinal data from China. Exploiting the opening of a Western-style fast-food restaurant in a particular community, we conduct a transition analysis to make a more convincing causal interpretation than the standard cross-sectional or fixed-effects approach. Considering several measures of fatness, we find no robust evidence of Western fast food having a substantial effect overall, but there is some indication of effect heterogeneity.  相似文献   
116.
以陆培等十位诗社成员为中心,从相关原始资料补充考订了清代诗人的生卒年及生平介绍,以期为日后编纂《全清诗》以及地方诗歌文献之类提供参考。  相似文献   
117.
Through travel diaries and interviews with newly retired urban residents in Sweden our aim was to explore (1) mobility patterns in the transition to retirement, (2) the influence of space–time restrictions and resources on mobility and (3) the meaning and embodied experience of mobility. This time-geographic study contributes with knowledge on how mobility is influenced by individual, social and geographical contexts. Illustrated by four cases, our result show that retirement changes the preconditions for mobility and creates new space–time restrictions. To spend more time on projects that were previously carried out outside working time, such as caring for grandchildren, volunteer work and household responsibilities, influenced the informants’ demands for mobility and choice of transport mode. However, the informants have resources that can be seen as strategies to overcome space–time restrictions. Most of the informants found it important to structure the day, to some it was vital to have something to do during the day while others enjoyed the possibility to take each day as it comes. Everyday mobility was a way of forming a structure by getting out of the house, either just for a walk or for making errands. The informants’ embodied experiences of mobility influenced their choice to walk and cycle for transport for the reasons of comfort, get fresh air, or simply to get out of the house. The daily mobility pattern that was established was a result of individual preferences and resources as well as negotiations with family members. We conclude that the transition to retirement is a period when new mobility patterns are considered, evaluated and practiced.  相似文献   
118.
Land Use and Land Cover (LULC) changes have profound impacts on the functioning of (agro)ecosystems and have potential to mitigate global climate change. However, we still lack interdisciplinary methods to project future LULC scenarios at spatial scales that are relevant for local decision making and future environmental assessments. Here we apply an interdisciplinary approach to develop spatially explicit projections of LULC at a resolution of 30 × 30 m informed by historic relationships between LULC and their key drivers, within the context of the four qualitative scenarios of global shared socioeconomic pathways. We apply this methodology to a case study in the Zona da Mata, Brazil, which has a history of major LULC changes. The analysis of LULC changes from 1986 to 2015 indicates that pasture area decreased from 76 to 58 % of total area, while forest areas increased from 18 to 24 %, and coffee from 3 to 11 %. Environmental protection legislation, rural credit for smallholder farmers, and demand for agricultural and raw products were identified as main drivers of LULC changes. Projected LULC for 2045 strongly depends on the global socioeconomic pathway scenarios, and forest and coffee areas may increase substantially under strong government measures in the environmentally conscious Green Road scenario or decrease in the high consumption Rocky Road scenario. Our study shows that under the set of drivers during the past three decades reforestation can go hand in hand with increase of agricultural production, but that major and contrasting changes in LULC can be expected depending on the socioeconomic pathway that will be followed in the future. To guide this process, LULC scenarios at the local scale can inform the planning of local and regional development and forest conservation.  相似文献   
119.
Rural residential land transition (RRLT) dominates rural land use transition. Therefore, analysing the laws of transition and differentiation of land use is not only the basis for the differential management of rural residential areas but key to the sustainable use of rural land. This study constructs a conceptual model of RRLT using multi-period remote sensing monitoring data based on a comprehensive index method, ArcGIS, and FRAGSTATS landscape pattern analysis, among others. It also analyses the characteristics of the transition extent, transition trend, transition morphology, and transition intensity of rural residential land in the Beijing-Tianjin-Hebei (BTH) region from 1980 to 2018. The results show that, from a vertical comparison of long time series, the transition extent is characterised by a process of ‘slow growth—expanding start—fast expansion—slowing down’; the transition trend is characterised by an increase in the amount of cultivated land occupied by rural residential land, followed by a large number of rural residential land is reclaimed as cultivated land; the transition morphology is characterised by an increase in mean patch size and degree of irregularity, as well as aggregation; and the transition intensity is characterised by fluctuations in the process of ‘small-scale reduction—small-scale growth—substantial growth—small-scale growth and reduction’. A horizontal comparison of counties in the BTH region reveals a long-lasting and active growth trend in transition extent and transition intensity in the Beijing-Tianjin region, and a gradually slowing trend in the areas around the region. The transition morphology features of the northwest Hebei region are more prominent, and show that the scale of rural settlements is small, the plaques fragmented and irregular, and the layout more scattered. The BTH region should formulate a differentiated transition direction for rural residential areas based on the different functional areas, and play into the agglomeration, scale, and synergy effects of urban agglomerations. It should also coordinate and improve the human–land relationship in rural areas, and construct an orderly and densely distributed pattern of urban and rural spatial development with a reasonable layout and complementary functions.  相似文献   
120.
Recent evidence on the “fertility rebound” offers credence to the idea that, from the onset of early industrialization to the present day, the dynamics of fertility can be represented by an N-shaped curve. An overlapping generations model with parental investment in human capital can account for these observed movements in fertility rates during the different stages of demographic change. A demographic transition with declining fertility emerges at the intermediate stage, when parents engage on a child quantity–quality trade-off. At later stages, however, the process of economic growth generates sufficient resources so that households can rear more children while still providing the desirable amount of education investment per child.  相似文献   
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