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171.
172.
C. Niessen  K. Eyferth 《Safety Science》2001,37(2-3):187-202
This paper reviews the development of a model of the air traffic controller's mental image, ‘picture’, or situation awareness, used for controlling air traffic. The computerised model's development, origins and theoretical basis are outlined, and the model is described in some detail in the context of current air traffic operations. The model can be utilised to explore the potential impacts of future automation on the cognitive performance of the air traffic controller. The general potential contributions of the area of cognitive modelling to system design and training in accelerating industries such as air traffic control, are also discussed.  相似文献   
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174.
Fuelwood is one of the major sources of energy in the domestic sector across the rural areas, especially in the developing regions across the world. The Northeastern Himalayan state of Manipur is dominated by the tribal population that largely depends on fuelwood from the nearby forest area. The entire dependence on forests for energy resources is affecting the sustainability of the forest ecosystem in the region, thus indicating the livelihood conditions. Since land-use land-cover change is the key driver to the change in resource availability of a region, the present study has tried to analyze the land-cover changes over a period 28 years. The second major component affecting resource availability is the increasing population pressure that leads to changes in the land dynamics, which directly affect the resource production. Based on the existing consumption pattern, the total consumption of fuelwood in the watershed ranges from a minimum of 289.992 tons/year to a maximum of 3545.719 tons/year with an average of 1561.956 tons/year in the year 2009 and simulated fuelwood consumption for the year 2021 is around 1469.260 tons/year. Nine different probable scenarios of resource are proposed to calculate the stress value that can be used by the policy-makers and planners for suitable policy implementation at the micro level with a complex social system.  相似文献   
175.
Abstract

This paper takes poverty-stricken county as the basic unit, and selects net income per peasant to study the poverty status in Hebei Province during 1986–2000. Temporal and spatial changes of poverty-stricken areas are analyzed. The result shows that poverty-stricken areas in Hebei Province distributed concentratedly and the areas decreased during 1986–2000, the net income per peasant was on the rise with an increasing speed in off-poverty counties being slightly higher than that in poverty-stricken counties, but the growth rate was extremely unstable, rising slowly in off-poverty counties while dropping in poverty-stricken counties. The main driving forces that influenced temporal and spatial changes were economic development of the whole province, ecological environment quality, infrastructure conditions and radiation of the key city. On this basis, some anti-poverty countermeasures suitable to local conditions are proposed.  相似文献   
176.
This paper tries to identify the characters that might affect interprovincial migrants’ decisions and examine how and why the influence of these characters changed over time individually and synthetically in China during 1985–2005. We have investigated six types of factors, namely, distance, population density, income, employment structure, house price, and migration stock. In addition, we apply the identified factors with a multiple stepwise regression model to a longitudinal dataset, which consists of interprovincial migration flows over the last two decades in China. It is found that different factors have disparate impacts on migration in China, and they can be decomposed into push force in origin area and pull force in destination area. Factors shaping China’s interprovincial migration have shifted from traditional factors such as distance to economic factors such as income and employment structure. This paper suggests that more attention should be paid to obtain detailed migration data with spatial information and develop applicable models for migration processes. Our analysis provides references for development planners and policymakers to develop sound population policies to achieve regional sustainable development in China.  相似文献   
177.
综合应用型人才培养是当前经济社会发展人才需求的迫切需要.安全工程是一门综合性很强的学科,基础理论和实践环节两者缺一不可,是输送综合应用型人才的重要学科之一.实验教学是安全工程学科教育培养体系中的重要组成部分,是工程人才技能培养的基础.实验教学改革研究对激发学生的探索能力、实践能力和主观能动性意义重大.笔者综述了我国安全工程实验教学现状及存在的问题;分析了面向培养综合应用型工程人才的积极意义;介绍了福州大学安全工程实验教学改革的四“转变”模式,为我国安全工程实验教学改革指出了方向.从以往几届毕业生反馈得知,很好地提高了学生的综合素质和动手能力.  相似文献   
178.
We analyzed the effects of changes in land cover on the water balance in Spain’s Marina Baixa County, on the Mediterranean coast. To reveal how different land management strategies have affected the area’s environment, four municipalities within the same catchment were studied: Benidorm, Callosa d’en Sarrià, Beniardà, and Guadalest. In the municipalities of Callosa and Benidorm, the proportion of the area covered by woodland declined by 4.2% and 30.2%, respectively, and woodland was replaced by agriculture and urban development. The abandonment of farmland produced a 17% increase in the proportion of the area covered by vegetation in Guadalest and Beniardá, where frequent forest fires have exacerbated a decrease in the area of pine woodland. Tourism development in Benidorm has been accompanied by an increase in the transportation infrastructure and by an expansion of areas with an impermeable surface, with the lowest level of infiltration into the aquifer system. These changes have generated a net water deficit in Callosa and Benidorm of more than 6 Mm3/year, creating a high demand for water imported from other municipalities (Guadalest and Beniardá) or from outside of the county to maintain the sustainability of the current water management strategies. The Marina Baixa case study is representative of many of the world’s coastal areas that are undergoing rapid urban development based on an inappropriate understanding of human progress based mainly on economic development and thus provides insights into water management in other areas.  相似文献   
179.
The correlation between climatic changes and the numbers of trees in the generations of Siberian spruce (Picea obovata Ledeb.) in subgoltsy tree stands of the Southern Urals was analyzed over the past 200 years. The results showed that the most abundant generations appeared in 1809–1816, 1821–1827, 1839–1845, 1850–1867, 1875–1887, 1891–1896, 1900–1904, 1911–1918, 1923–1932, 1944–1952, 1958–1966, and 1975–1995. Their formation proved to be related to the improvement of thermal conditions of the warm season during the five to seven years before and after the emergence of trees and conditions of the cold season in the year of their emergence, as well as to the periods of increased snow depth in late April in the years 27–32 of tree growth.  相似文献   
180.
三峡库区水源涵养重要区生态系统格局动态演变特征   总被引:4,自引:0,他引:4  
利用三期遥感分类数据为基础数据源,结合野外地面核查和生态空间分析方法,对三峡库区水源涵养重要区2000~2010年生态系统格局时空动态变化进行了分析。结果表明:研究区内各类生态系统空间分布差异较大,以森林和农田为主体生态系统;10a间,由于三峡水库蓄水淹没了大量农田和林地,导致森林生态系统和农田生态系统分别向湿地生态系统转化了179.99km2和191.27km2;其他生态系统(主要是人工表面)面积在时段内增加了506.63km2,主要是城镇建设占用部分森林和农田转换而来;时段内森林生态系统总的面积未发生较大减少主要是由于近年退耕还林、森林工程等生态工程的实施获得了大量补充;研究区后期的生态系统转化强度在逐渐增强,生态系统动态类型相互转化强度也显示出研究区生态系统类型的转化总体变差。  相似文献   
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