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121.
通过对太湖流域重污染区1999年和2007年的2期遥感影像数据解译结果的分析,获取了太湖流域重污染区主要土地利用类型的信息,分析了8年来研究区内土地利用与覆被变化趋势,并对区域内土地利用/覆被变化的驱动因子进行了探讨。结果表明,从1999~2007年间,太湖流域重污染区内耕地面积减少,而林地、建设用地、园地、水域总体呈增加的趋势,其中减少的耕地主要转化为建设用地。在区域结构中,影响土地利用结构变化的驱动力因素主要是经济的发展、城市化进程推进、人口增长以及政策因素这4个方面,而研究区内经济的快速发展和人口的增长成为土地利用/覆被变化的关键因素。 相似文献
122.
Introduction: Veterans are at heightened risk of being in a motor-vehicle crash and many fail on-road driving evaluations, particularly as they age. This may be due in part to the high prevalence of age-associated conditions impacting cognition in this population, including neurodegenerative diseases (e.g., Alzheimer’s Disease) and acquired neurological conditions (e.g., cerebrovascular accident). However, understanding of the impact of referral diagnosis, age and cognition on Veterans’ on-road driving performance is limited. Methods: 109 Veterans were referred for a driving evaluation (mean age = 72.0, SD = 11.5) at a driving assessment clinic at the Minneapolis Veterans Affairs Healthcare System. Of the 109 Veterans enrolled, 44 were referred due to a neurodegenerative disease, 37 due to an acquired neurological condition, and 28 due to a non-neurological condition (e.g., vision loss). Veterans completed collection of health history information and administration of cognitive tests assessing visual attention, processing speed, and executive functioning, as well as a standardized, on-road driving evaluation. Results: A total of 17.9% of Veterans failed the on-road evaluation. Clinical diagnostic group was not associated with failure rate. Age was not associated with failure rates in the full sample or within diagnostic groups. After controlling for age, poorer processing speed and selective/divided attention were associated with higher failure rates in the full sample. No cognitive tests were associated with failure rates within diagnostic groups. Conclusion: Referral diagnosis and age alone are not reliable predictors of Veterans’ driving performance. Cognitive performance, specifically speed of processing and attention, may be helpful in screening Veterans’ driving safety. Practical Applications: Clinicians tasked with assessing Veterans’ driving safety should take into account cognitive performance, particularly processing speed and attention, when making decisions regarding driving safety. Age and referral diagnosis, while helpful information, are insufficient to predict outcomes on driving evaluations. 相似文献
123.
Introduction: This study investigated the separate impact of first eye and second eye cataract surgery on driving performance, as measured on a driving simulator. Method: Forty-four older drivers with bilateral cataract aged 55+ years, awaiting first eye cataract surgery participated in a prospective cohort study. They completed a questionnaire, visual tests and a driving simulator assessment at three time points: before first eye, after first eye, and after second eye cataract surgery. Generalized Estimating Equation Poisson or linear regression models were undertaken to examine the change in four driving outcomes of interest after adjusting for cataract surgery and other potential confounders. Results: The rate of crashes/near crashes decreased significantly by 36% (incidence rate ratio (IRR) 0.64, 95% CI 0.47–0.88, p = 0.01) after first eye surgery and 47% (IRR 0.53, 95% CI 0.35–0.78, p < 0.001) after second eye surgery, compared to before first eye cataract surgery, after accounting for confounders. The rate of crashes/near crashes also decreased with better contrast sensitivity (IRR 0.69, 95% CI 0.48–0.90, p = 0.041). A separate model found that time spent speeding 10 kilometers per hour or more over the limit after second eye surgery was significantly less (0.14 min, p = 0.002), compared to before first eye surgery, after accounting for confounders. As contrast sensitivity improved, the duration of speeding also decreased significantly by 0.46 min (p = 0.038). There were no statistically significant changes in lane excursions or speed variation. Practical applications: The findings highlight the importance of timely first and second eye cataract surgery to ensure driver safety, especially as older drivers wait for second eye cataract surgery. It also provides further evidence that contrast sensitivity is probably a better predictor of driving ability in older drivers with cataract than visual acuity, the measure on which driver licensing requirements are currently based, and should also be used when assessing fitness to drive. 相似文献
124.
Socio-economic driving forces of land-use change in Kunshan, the Yangtze River Delta economic area of China 总被引:28,自引:0,他引:28
This paper analyzes characteristics, major driving forces and alternative management measures of land-use change in Kunshan, Jiangsu province, China. The study used remote sensing (RS) maps and socio-economic data. Based on RS-derived maps, two change matrices were constructed for detecting land-use change between 1987 and 1994, and between 1994 and 2000 through pixel-to-pixel comparisons. The outcomes indicated that paddy fields, dryland, and forested land moderately decreased by 8.2%, 29% and 2.6% from 1987 to 1994, and by 4.1%, 7.6% and 8% from 1994 to 2000, respectively. In contrast, the following increased greatly from 1987 to 1994: artificial ponds by 48%, urban settlements by 87.6%, rural settlements by 41.1%, and construction land by 511.8%. From 1994 to 2000, these land covers increased by 3.6%, 28.1%, 23.4% and 47.1%, respectively. For the whole area, fragmentation of land cover was very significant. In addition, socio-economic data were used to analyze major driving forces triggering land-use change through bivariate analysis. The results indicated that industrialization, urbanization, population growth, and China's economic reform measures are four major driving forces contributing to land-use change in Kunshan. Finally, we introduced some possible management measures such as urban growth boundary (UGB) and incentive-based policies. We pointed out that, given the rapidity of the observed changes, it is critical that additional studies be undertaken to evaluate these suggested policies, focusing on what their effects might be in this region, and how these might be implemented. 相似文献