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利用日平均数调剂法改进药房药品调剂方法的研究
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作者 杨姜德 徐挺兰 +2 位作者 程林鹏 刘勇华 漆世捷 《中国医药导报》 CAS 2009年第36期151-152,共2页
目的:探索改进门诊药房药品调剂的方法。方法:通过建立专门的药房布局,运用日平均数调剂法,改进药房调剂方法,提高药学服务质量。结果:门诊药房实行日平均数调剂法后大大提高了处方调配速度和准确率,使更多的药师可以投入到直接面对患... 目的:探索改进门诊药房药品调剂的方法。方法:通过建立专门的药房布局,运用日平均数调剂法,改进药房调剂方法,提高药学服务质量。结果:门诊药房实行日平均数调剂法后大大提高了处方调配速度和准确率,使更多的药师可以投入到直接面对患者及医生、护士以合理用药为核心的药学服务当中去。结论:本方法简便快捷、准确,在实践当中有很好的应用价值。 展开更多
关键词 日平均数调剂法 药学服务 调剂
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例谈中考不等式(组)应用题
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作者 张振兴 《教育实践与研究(中学版)(B)》 1999年第2期33-34,共2页
请看以下例题: 例1.(98’河北省中考题)某工厂现有甲种原料360千克,乙种原料290千克,计划用这两种原料生产A、B两种产品,共50件。已知生产一件A种产品,需用甲种原料9千克、乙种原料3千克,可获利润700元;生产一件B种产品,需用甲种原料4千... 请看以下例题: 例1.(98’河北省中考题)某工厂现有甲种原料360千克,乙种原料290千克,计划用这两种原料生产A、B两种产品,共50件。已知生产一件A种产品,需用甲种原料9千克、乙种原料3千克,可获利润700元;生产一件B种产品,需用甲种原料4千克,乙种原料10千克。可获利润1200元。 (1)按要求安排A、B两种产品的生产件数,有哪几种方案?请你给设计出来; 展开更多
关键词 不等式组 旅行社 中考题 客车 日平均数 例谈 可获利 全票价 解应用题 原料9
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Effects of Snow Cover on Ground Thermal Regime: A Case Study in Heilongjiang Province of China 被引量:2
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作者 LI Xiaofeng ZHENG Xingming +3 位作者 WU Lili ZHAO Kai JIANG Tao GU Lingjia 《Chinese Geographical Science》 SCIE CSCD 2016年第4期527-538,共12页
The important effects of snow cover to ground thermal decades. In the most of previous research, the effects were usually regime has received much attention of scholars during the past few evaluated through the numeri... The important effects of snow cover to ground thermal decades. In the most of previous research, the effects were usually regime has received much attention of scholars during the past few evaluated through the numerical models and many important results are found. However, less examples and insufficient data based on field measurements are available to show natural cases. In the present work, a typical case study in Mohe and Beijicun meteorological stations, which both are located in the most northern tip of China, is given to show the effects of snow cover on the ground thermal regime. The spatial (the ground profile) and time series analysis in the extremely snowy winter of 2012-2013 in Heilongjiang Province are also performed by contrast with those in the winter of 2011-2012 based on the measured data collected by 63 meteorological stations, Our results illustrate the positive (warmer) effect of snow cover on the ground temperature (GT) on the daily basis, the highest difference between GT and daily mean air temperature (DGAT) is as high as 32.35℃. Moreover, by the lag time analysis method it is found that the response time of GT from 0 cm to 20 cm ground depth to the alternate change of snow depth has 10 days lag, while at 40 cm depth the response of DGAT is not significant. This result is different from the previous research by modeling, in which the resnonse denth of ground to the alteration of snow depth is far more than 40 cm. 展开更多
关键词 snow cover ground temperature lag time analysis spline mean difference between ground temperature and air temperature(DGAT)
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Variations in Soil Temperature at BJ Site on the Central Tibetan Plateau 被引量:7
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作者 WAN Guoning YANG Meixue WANG Xuejia 《Journal of Mountain Science》 SCIE CSCD 2012年第2期274-285,共12页
The temporal and spatial variation in soil temperature play a significant role in energy and water cycle between land surface and atmosphere on the Tibetan Plateau.Based on the observed soil temperature data(hourly d... The temporal and spatial variation in soil temperature play a significant role in energy and water cycle between land surface and atmosphere on the Tibetan Plateau.Based on the observed soil temperature data(hourly data from 1 January 2001 to 31 December 2005)obtained by GAME-Tibet,the diurnal,seasonal and interannual variations in soil temperature at BJ site(31.37°N,91.90°E; 4509 m a.s.l.)near Naqu in the central Tibetan Plateau were analyzed.Results showed that the average diurnal variation in soil temperature at 4 and 20 cm depth can be described as sinusoidal curve,which is consistent with the variation of solar radiation. However,the average diurnal variation in soil temperature under 60 cm was very weak.The average diurnal amplitude in soil temperature decreased by the exponential decay function with the increase of soil depth(R2=0.92,p〈0.01).It is demonstrated that the average diurnal maximum soil temperature decreased by the exponential decay function with the increase of soil depth(R2=0.78,p〈0.01).In contrast, the average diurnal minimum soil temperature increased by the exponential grow function with increasing of soil depth(R2=0.86,p〈0.01).There were a linear negative correlation between the average annual maximum Ts and soil depth(R2=0.96, p〈0.01),a logarithmic function relationship between the average annual minimum soil temperature and soil depth(R2=0.92,p〈0.01).The average seasonal amplitude in soil temperature followed the exponential decay function with the increase of soil depth(R2=0.98,p〈0.01).The mean annual soil temperature in each layer indicated a warming trend prominently.During the study period,the mean annual soil temperature at 4,20,40,60,80,100,130, 160,200 and 250 cm depth increased by 0.034,0.041, 0.061,0.056,0.062,0.050,0.057,0.051,0.047 and 0.042℃/a,respectively. 展开更多
关键词 Tibetan Plateau Land-atmosphere interaction Soil temperature Climate warming
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Analysis on Changes of Basic Climatic Elements and Extreme Events in Xinjiang, China during 1961-2010 被引量:22
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作者 JIANG Yuan-An CHEN Ying +4 位作者 ZHAO Yi-Zhou CHEN Peng-Xiang YU Xing-Jie FAN Jing BAI Su-Qin 《Advances in Climate Change Research》 SCIE 2013年第1期20-29,共10页
By using the observation data from 89 weather stations in Xinjiang during 1961-2010, this paper analyzed the basic climatic elements including temperature, precipitation, wind speed, sunshine duration, water vapor pre... By using the observation data from 89 weather stations in Xinjiang during 1961-2010, this paper analyzed the basic climatic elements including temperature, precipitation, wind speed, sunshine duration, water vapor pressure, and dust storm in the entire Xinjiang and the subareas: North Xinjiang, Tianshan Mountains, and South Xinjiang. The results indicate that from 1961 to 2010 the annual and seasonal mean temperatures in the entire Xinjiang show an increasing trend with the increasing rate rising from south to north. The increasing rate of annual mean minimum temperature is over twice more than that of the annual mean maximum temperature, contributing much to the increase in the annual averages. The magnitude of the decrease rate of low-temperature days is larger than the increase rate of high-temperature days. The increase of warm days and warm nights and the decrease of cold days and cold nights further reveal that the temperature increasing in Xinjiang is higher. In addition, annual and seasonal rainfalls have been increasing. South Xinjiang experiences higher increase in rainfall amounts than North Xinjiang and Tianshan Mountains. Annual rainy days, longest consecutive rainy days, the daily maximum precipitation and extreme precipitation events, annual torrential rain days and amount, annual blizzard days and amount, all show an increasing trend, corresponding to the increasing in annual mean water vapor pressure. This result shows that the humidity has increased with temperature increasing in the past 50 years. The decrease in annual mean wind speed and gale days lessen the impact of dust storm, sandstorm, and floating dust events. The increase in annual rainy days is the cause of the decrease in annual sunshine duration, while the increase in spring sunshine duration corresponds with the decrease in dust weather. Therefore, the increase in precipitation indicators, the decrease in gales and dust weather, and the increasing in sunshine duration in spring will be beneficial to crops growth. 展开更多
关键词 Xinjiang temperature precipitation dust storm extreme climate event
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Changes in Climatic Factors and Extreme Climate Events in Northeast China during 1961-2010 被引量:11
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作者 ZHAO Chun-Yu WANG Ying +5 位作者 ZHOU Xiao-Yu CUI Yan LIU Yu-Lian SHI Da-Ming YU Hong-Min LIU Yu-Ying 《Advances in Climate Change Research》 SCIE 2013年第2期92-102,共11页
This study focuses on examining the characteristics of climate factors and extreme climate events in Northeast China during 1961- 2010 by using daily data from 104 stations, including surface air temperature, precipit... This study focuses on examining the characteristics of climate factors and extreme climate events in Northeast China during 1961- 2010 by using daily data from 104 stations, including surface air temperature, precipitation, wind speed, sunshine duration, and snow depth. Results show that annual mean temperature increased at a significant rate of 0.35℃ per decade, most notably in the Lesser Khingan Mountains and in winter. Annual rainfall had no obvious linear trend, while rainy days had a significant decreasing trend. So, the rain intensity increased. High-temperature days had a weak increasing trend, and low-temperature days and cold wave showed significant decreasing trends with rates of 3.9 d per decade and -0.64 times per decade, respectively. Frequency and spatial scope of low-temperature hazard reduced significantly. Warm days and warm nights significantly increased at 1.0 and 2.4 d per decade, while cold days and cold nights decreased significantly at -1.8 and -4.1 d per decade, respectively. The nighttime warming rate was much higher than that for daytime, indicating that nighttime warming had a greater contribution to the overall warming trend than daytime warming. The annual mean wind speed, gale days, and sunshine duration had significant decreasing trends at rates of-0.21 m s-1 per decade, -4.0 d per decade and -43.3 h per decade, respectively. The snow cover onset dates postponed at a rate of 1.2 d per decade, and the snow cover end date advanced at 1.5 d per decade, which leads to shorter snow cover duration by -2.7 d per decade. Meanwhile, the maximum snow depth decreased at -0.52 cm per decade. In addition, the snow cover duration shows a higher correlation with precipitation than with temperature, which suggests that precipitation plays a more important role in maintaining snow cover duration than temperature. 展开更多
关键词 climatic factors extreme climate events climate change Northeast China
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Wind Speed Forecasting Based on ARMA-ARCH Model in Wind Farms 被引量:3
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作者 He Yu Gao Shan Chen Hao 《Electricity》 2011年第3期30-34,共5页
Wind speed forecasting is signif icant for wind farm planning and power grid operation. The research in this paper uses Eviews software to build the ARMA (autoregressive moving average) model of wind speed time series... Wind speed forecasting is signif icant for wind farm planning and power grid operation. The research in this paper uses Eviews software to build the ARMA (autoregressive moving average) model of wind speed time series, and employs Lagrange multipliers to test the ARCH (autoregressive conditional heteroscedasticity) effects of the residuals of the ARMA model. Also, the corresponding ARMA-ARCH models are established, and the wind speed series are forecasted by using the ARMA model and ARMA-ARCH model respectively. The comparison of the forecasting accuracy of the above two models shows that the ARMA-ARCH model possesses higher forecasting accuracy than the ARMA model and has certain practical value. 展开更多
关键词 short-term wind speed forecasting ARMA model ARCH effect volatility clustering
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On necessary and sufficient conditions for the self-normalized central limit theorem In Honor of Professor Chuanrong Lu on His 85th Birthday 被引量:1
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作者 Qiman Shao 《Science China Mathematics》 SCIE CSCD 2018年第10期1741-1748,共8页
Let X_1, X_2,... be a sequence of independent random variables and S_n=sum X_1 from i=1 to n and V_n^2=sum X_1~2 from i=1 to n . When the elements of the sequence are i.i.d., it is known that the self-normalized sum S... Let X_1, X_2,... be a sequence of independent random variables and S_n=sum X_1 from i=1 to n and V_n^2=sum X_1~2 from i=1 to n . When the elements of the sequence are i.i.d., it is known that the self-normalized sum S_n/V_n converges to a standard normal distribution if and only if max1≤i≤n|X_i|/V_n → 0 in probability and the mean of X_1 is zero. In this paper, sufficient conditions for the self-normalized central limit theorem are obtained for general independent random variables. It is also shown that if max1≤i≤n|X_i|/V_n → 0 in probability, then these sufficient conditions are necessary. 展开更多
关键词 central limit theorem SELF-NORMALIZED independent random variables
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