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基于WOFOST模型与遥感数据同化的县级尺度玉米估产研究
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作者 钱凤魁 王化军 +3 位作者 王祥国 于远俊 辛家佶 顾汉龙 《沈阳农业大学学报》 CAS CSCD 北大核心 2024年第2期138-152,共15页
区域尺度的作物生长动态监测和产量预测对于保障粮食安全和农业政策的制定具有重要参考依据。遥感数据同化应用极大提高了作物估产的时效性和精度。为及时、准确地实现县级尺度粮食产量的估测,以及提升产量估测的精度,以辽宁省铁岭县为... 区域尺度的作物生长动态监测和产量预测对于保障粮食安全和农业政策的制定具有重要参考依据。遥感数据同化应用极大提高了作物估产的时效性和精度。为及时、准确地实现县级尺度粮食产量的估测,以及提升产量估测的精度,以辽宁省铁岭县为研究区,采用WOFOST(world food studies)模型与遥感同化相结合的方法对铁岭县玉米进行估产研究。通过采用扩展傅里叶幅度敏感性检验算法(extened Fourier amplitude sensitivity test,EFAST)敏感性分析方法实现玉米估产敏感性参数的分析,以及本地化;通过采用参数自动率定程序PEST(parameter estimation)实现参数的优化,验证结果为采样点产量的平均误差为852.39 kg·hm^(-2),模型模拟的精度达到92.82%。为进一步提高和优化模型估产精度,将遥感反演得到的叶面积指数采用集合卡尔曼滤波算法与模型模拟的叶面积指数进行数据同化,平均误差从同化前的852.39 kg·hm^(-2)降低为435.01 kg·hm^(-2),估产精度从92.82%提高到96.33%,有效提高了WOFOST模型估产的精度。结果表明:水分对玉米的生长发育限制并不大,其产量形成主要受光温影响,对温度、光能利用效率和最大同化速率有关的参数具有较高的敏感性;优化后的模型能够较好模拟铁岭县玉米生长发育情况,产量验证表明优化后的模型模拟的效果较好,但仍存在一定的误差;比值植被指数与叶面积指数的相关性最高,反演模型精度较好,反演结果表明叶面积指数在抽雄吐丝期差距较大,而在成熟期的差距不大;经过作物模型与遥感数据同化之后,估产的精度得到明显提高,说明遥感与作物模型同化是一种有效地提高作物估产和产量预测精度的方法。 展开更多
关键词 world food studies模型 遥感 数据同化 玉米估产 铁岭县
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Indoor tanning bed use and risk of food addiction based on the modified Yale Food Addiction Scale
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作者 Wen-Qing Li John E.McGeary +6 位作者 Eunyoung Cho Alan Flint Shaowei Wu Alberto Ascherio Eric Rimm Alison Field Abrar A.Qureshi 《The Journal of Biomedical Research》 CAS CSCD 2017年第1期31-39,共9页
The popularity of indoor tanning may be partly attributed to the addictive characteristics of tanning for some individuals.We aimed to determine the association between frequent indoor tanning,which we view as a sunog... The popularity of indoor tanning may be partly attributed to the addictive characteristics of tanning for some individuals.We aimed to determine the association between frequent indoor tanning,which we view as a sunogate for tanning addiction,and food addiction.A total of 67,910 women were included from the Nurses' Health Study II.In2005,we collected information on indoor tanning during high school/college and age 25-35 years,and calculated the average use of indoor tanning during these periods.Food addiction was defined as ≥3 clinically significant symptoms plus clinically significant impairment or distress,assessed in 2009 using a modified version of the Yale Food Addiction Scale.Totally 23.3%(15,822) of the participants reported indoor tanning at high school/college or age 25-35 years.A total of 5,557(8.2%) women met the criteria for food addiction.We observed a dose-response relationship between frequency of indoor tanning and the likelihood of food addiction(P_(trend)〈 0.0001),independent of depression,BMI,and other confounders.Compared with never indoor tanners,the odds ratio(95%confidence interval) of food addiction was 1.07(0.99-1.17) for average indoor tanning 1-2 times/year,1.25(1.09-1.43) for 3-5times/year,1.34(1.14-1.56) for 6-11 times/year,1.61(1.35-1.91) for 12-23 times/year,and 2.98(1.95-4.57) for 24 or more times/year.Frequent indoor tanning before or at early adulthood is associated with prevalence of food addiction at middle age.Our data support the addictive property of frequent indoor tanning,which may guide intervention strategies to curb indoor tanning and prevent skin cancer. 展开更多
关键词 indoor tanning food addiction cohort study skin cancer epidemiology UV radiation
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Influence of Climate Change on Winter Wheat Growth in North China During 1950-2000 被引量:5
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作者 宋艳玲 Elisabeth SIMELTON +1 位作者 陈德亮 董文杰 《Acta meteorologica Sinica》 SCIE 2005年第4期501-510,共10页
The crop model World Food Studies (WOFOST) was tuned and validated withmeteorological as well as winter wheat growth and yield data at 24 stations in 5 provinces of NorthChina from 1997 to 2003. The parameterization o... The crop model World Food Studies (WOFOST) was tuned and validated withmeteorological as well as winter wheat growth and yield data at 24 stations in 5 provinces of NorthChina from 1997 to 2003. The parameterization obtained by the tuning was then used to model theimpacts of climate change on winter wheat growth for all stations using long-term weather data from1950 to 2000. Two simulations were made, one with all meteorological data (rainfed) and the otherwithout water stress (potential). The results indicate that the flowering and maturity datesoccurred 3.3 and 3 days earlier in the 1990s than that in the 1960s due to a 0.65℃ temperatureincrease. The simulated rainfed yields show that the average drought induced yields (potential minusrainfed yields) have decreased by 9.7% over the last 50 years. This is to be compared with a 0.02%decrease in yield if the precipitation limit is lifted. Although the precipitation during thegrowing season has decreased over the last 50 years, the drought effects on the rainfed yieldsremained to be practically unchanged as the spring precipitation did not decrease markedly. 展开更多
关键词 crop growth model world food studies (WOFOST) climate change winter wheat north China
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