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41.
The Late Cluster variety of hops when introduced to Kashmir (India) from USA gave two flowering flushes in a growing season, thus giving two harvests. By adjusting the date of dressing (root pruning) from December to May 15 the abnormal flowering behaviour of the plant could be altered from two flushes to only one. Plants dressed late in spring, April 15 to May 1, gave the highest cone yield which was expressed in only one harvest. This also produced the highest α-acids content. 相似文献
42.
在逐日数据维护中,对一些不正常的数据进行替换,对缺测时次资料进行重新卸载保存,保存正确数据,以保证B文件的完整、正确。本文主要介绍了进行逐日数据维护时需要注意的几个方面。 相似文献
43.
为了解大跨度日光温室在典型天气下室内微气候环境特点,对沈阳地区一座跨度12m日光温室阴天、晴天情况下的室内外太阳辐射、空气温度、空气相对湿度以及各壁(土壤、薄膜、后坡、墙体)内表面的热流量、表面温度进行了测试。1月份阴天、晴天测试结果显示:晴天时太阳辐射透过率日均值近60%;揭帘后至夜间(9:00—23:00),晴天室内空气平均温度比阴天高5.5℃;夜间(18:00-23:00)0.2m土壤温度平均值晴天为11.6℃、阴天为9.9℃;前屋面、后坡几乎全天从室内吸热,土壤及后墙向室内平均放热量是阴天的1.5倍;晴天室内空气日均相对湿度为87%,阴天为93%。 相似文献
44.
The effect of age and time of day on objective and subjective sleepiness in professional drivers was investigated during a simulated driving task. Thirty-six young and middle-aged professional males drivers, free from any sleep disorder, took part in two simulated driving sessions; one carried out in the afternoon (between 2 and 4 p.m.) the other in the evening (between 11 p.m. and 1 a.m.). Half of each age group drove in a low traffic condition while the second half drove in a heavy traffic condition. Throughout the driving task, subjects' electroencephalogram and Karolinska sleepiness scale (KSS) scores were recorded. Visual analog scales measuring alertness and sleepiness levels were also completed before and after the driving. After each session, subjects filled out the NASA-TLX questionnaire and were asked if they had felt sleepy during the driving. Young professional drivers presented a significant decrease in alertness (raise of the spectral power in the alpha band) in the low traffic condition and a strong propensity to sleep during the evening test in contrast to middle-aged professional drivers. 相似文献
45.
Yasufumi Katsura Pathom Attaviriyanupap Yoshihiko Kataoka 《Electrical Engineering in Japan》2012,178(3):11-20
In this research, the fundamental premises for deregulation of the electric power industry are reevaluated. The authors develop a simple model to represent the wholesale electricity market with a highly congested network. The model is developed by simplifying the power system and market in the New York ISO based on available data for the New York ISO in 2004 along with some estimation. Based on the developed model and construction cost data from the past, the economic impact of transmission line addition on market participants and the impact of deregulation on power plant additions in a market with transmission congestion are studied. Simulation results show that market signals may fail to facilitate proper capacity additions and results in the undesirable overconstruction and insufficient construction cycle of capacity addition. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(3): 11–20, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21013 相似文献
46.
改进网格法及其在雷电参数统计中的应用 总被引:1,自引:0,他引:1
为改善采用网格法得出雷电参数统计值可信度与空间精度不够高的缺陷而提出了改进网格法,该方法将传统网格法的单一参数(网络面积)扩展到双参数(网络面积和观测范围)。以重庆市某年雷电定位数据为例,比较分析了传统网格法和改进网格法在雷电日、雷电小时、地闪密度3类雷电参数统计时的差异。统计结果表明,采用改进网格法时3类统计值均不会随网格精度的提高而出现显著变化,其可信度及空间精度均高于传统网格法,且所得雷电参数的物理意义更明确。改进网格法可为提高差异化防雷设计提供支持。 相似文献
47.
48.
以电话网话务量定义为切入点,指出当前工程设计过程中一般采用的基础话务量调查、统计、取定的办法和存在的问题,并针对某省GSM网一个完整年度的用户忙时平均话务量做遍历考察和研究分析,绘制全年话务量波动性曲线,对工程设计中遇到的话务量指标进行量化计算和对比,统计全年忙日出现的概率。 相似文献
49.
目的 监测2015~2017年间某地区部分学校采购食品中二氧化硫的残留情况, 及时排除学校食堂的食品安全隐患。方法 从某地区163所学校抽取干制蔬菜、干制食用菌和藻类、粉丝类、腐竹类、食糖、食用淀粉、香辛料7类样品共计847份, 检测二氧化硫残留量。结果 820份符合中国卫生标准, 合格率达96.81%。7类食品中食糖、粉丝粉条和香辛料类样品结果均合格, 干制蔬菜、干制的食用菌和藻类、淀粉和腐竹类存在超标样本, 其中二氧化硫残留超标最严重的是干制蔬菜中的黄花菜, 超标率达33.31%; 其次是干制的食用菌和藻类中的银耳, 超标率达20.00%, 最后是淀粉和腐竹, 超标率分别为7.43%和1.33%。对二氧化硫超标的食品已及时与学校沟通并做出风险预警, 及时排除了安全隐患。结论 学校食堂所采购的食品中, 黄花菜、银耳中二氧化硫超标严重, 淀粉和腐竹中二氧化硫也存在超标情况, 应加强监管。 相似文献
50.
《Contact lens & anterior eye》2019,42(4):373-379
PurposeTo gain a better understanding of eye care professionals’ (ECPs) perceptions regarding the benefits of silicone hydrogel (SiH) daily disposable contact lenses (DDCL), particularly with respect to health, comfort and patient satisfaction.MethodsA survey was conducted with 300 ECPs in the United States, United Kingdom and Japan during November 2017. The survey comprised 34 statements relating to SiH DDCLs, to which the ECPs provided their level of agreement using a 6 point Likert scale. A minimum of 70% agreement was set to define majority agreement. Categories of statements included Health, Comfort, Patient Experience, and Standard of Care.ResultsECPs rated the highest levels of agreement to perceptions within the Patient Experiences and Health categories. The six statements receiving the highest ratings were “Silicone hydrogel 1 day lenses satisfy today’s patients’ demanding lifestyles” (93% agreement); “Silicone hydrogel 1 day lenses are the best choice to safeguard my patients’ eye health related to contact lens wear” (92%); “Silicone hydrogel 1 day lenses provide the best benefits to my patients” (92%); “Silicone hydrogel 1 day lenses provide better long term eye health for my patients than hydrogel 1 day lenses” (91%); “Silicone hydrogel is the healthiest lens material for my daily disposable patients” (90%); and “Silicone hydrogel 1 day lenses provide a better wearing experience for my patients than hydrogel 1 day lenses” (90%).ConclusionECPs perceive that SiH DDCLs offer long-term eye health and comfort for the patient and although the ECPs surveyed would not necessarily prescribe SiH DDCLs to all their patients, they would prescribe them to most of their patients. The results support the premise that while ECPs consider SiH 1 day contact lenses as the current “standard of care”; the principal barrier continues to be the perceived higher cost of these lenses. 相似文献