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老年骨质疏松症流行病学调查及预防措施研究 被引量:64
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作者 赵宗权 吴贻红 +4 位作者 汤振源 丁志良 张豪 施美华 马庆华 《中国骨质疏松杂志》 CAS CSCD 北大核心 2019年第7期994-997,共4页
目的探讨老年骨质疏松症流行病学调查及预防措施。方法 2017年6月至2018年6月,对辖区5432例老年人进行骨质疏松症调查。结果骨质疏松症发生率为12.44%;腰椎2~4部位骨密度平均为(0.820±0.111) g/cm^2,股骨颈平均骨密度为(0.818±... 目的探讨老年骨质疏松症流行病学调查及预防措施。方法 2017年6月至2018年6月,对辖区5432例老年人进行骨质疏松症调查。结果骨质疏松症发生率为12.44%;腰椎2~4部位骨密度平均为(0.820±0.111) g/cm^2,股骨颈平均骨密度为(0.818±0.103) g/cm^2,股骨颈粗隆平均骨密度为(0.712±0.100) g/cm^2,Ward三角区平均骨密度为(0.704±0.112) g/cm^2;骨质疏松症患者女性比例、年龄、饮酒比例、日饮用牛奶量<250 mL/d比例、未口服钙片比例及体育锻炼<30 min/d比例分别为59.17%、(75.20±9.28)岁、60.95%、69.08%、65.83%、57.25%,明显高于无骨质疏松症者(P<0.05);Logistic回归分析显示女性、年龄是老年人发生骨质疏松的危险因素(OR=1.761、1.964,P<0.05),而日饮用牛奶量、口服钙片和体育锻炼是老年人发生骨质疏松的保护因素(OR=0.725、0.661和0.718,P<0.05)。结论本地区老年骨质疏松症发生比例较高,应根据相关危险因素采取有针对性的措施,以减少骨质疏松的发生。 展开更多
关键词 老年人 骨质疏松 危险因素 流行病学
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太湖流域圩区排涝分级调度影响研究 被引量:3
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作者 丁志良 胡子琛 孙凌凯 《水利水电技术(中英文)》 北大核心 2023年第2期10-18,共9页
【目的】近年来随着太湖流域圩区排涝能力建设,流域洪涝风险逐渐由圩区向圩外河道转移,圩区排涝与区域、流域防洪间的矛盾日益凸显,为缓解这一矛盾,【方法】研究提出了圩区排涝泵站的分级调度方案,并以武澄锡虞区为典型区域,采用水动力... 【目的】近年来随着太湖流域圩区排涝能力建设,流域洪涝风险逐渐由圩区向圩外河道转移,圩区排涝与区域、流域防洪间的矛盾日益凸显,为缓解这一矛盾,【方法】研究提出了圩区排涝泵站的分级调度方案,并以武澄锡虞区为典型区域,采用水动力模拟的手段,对不同降雨条件下调度方案改变对洪水演进过程的影响进行了研究,将分级调度方案与现状调度、减小动力及抬高起排三种方案进行了对比分析。【结果】结果显示,减小动力方案在遭遇高强度暴雨时无法及时排涝,导致圩区发生内涝灾害;抬高起排方案在利用圩区蓄水时未能有效利用圩外河道的行洪能力,无法有效降低圩外河道洪峰水位;分析提出的分级调度方案充分利用了圩内调蓄与圩外行洪能力,同时保障了圩内、外涝风险可控。【结论】结果表明,在合理的分级方案下,分级调查可以在确保圩内洪涝灾害风险可控的前提下降低圩外河道行洪压力,实现圩内-圩外洪涝风险的动态共担。 展开更多
关键词 洪水 分级调度 水动力模拟 太湖流域 圩区
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Research on Controlled Volume Operation Method of Large-scale Water Transfer Canal
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作者 ding zhiliang WANG Changde +1 位作者 XU Duo XIAO Hua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期47-59,共13页
The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control metho... The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control method for multi-reach canal system in series was established. In allusion to the deficiency of existing controlled volume algorithm, the improved controlled volume algorithm of the whole canal pools was proposed, and the simulation results indicated that the storage volume and water level of each canal pool could be accurately controlled after the improved algorithm had been adopted. However, for some typical discharge demand operating conditions, if the previously mentioned algorithm was adopted, then it certainly would cause some unnecessary gate adjustments, and consequently the disturbed canal pools would be increased. Therefore, the idea of controlled volume operation method of continuous canal pools was proposed, and corresponding algorithm was designed. Through simulating practical project, the results indicated that the new controlled volume algorithm proposed for typical operating conditions could comparatively and obviously reduce the number of regulated check gates and disturb canal pools for some typical discharge demand operating conditions, thus the control efficiency of canal system could be improved. 展开更多
关键词 canal operation controlled volume method of operation control algorithm SIMULATION
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