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121.
有效增强窗的节能效果是提高建筑节能水平的重要环节.根据湖南地区建筑节能的现有特点和调查结果分析,节能窗的设计应该多方面综合着手,从材料、窗型选择、遮阳措施等方面进行优化.  相似文献   
122.
This paper investigated the applicability and effects of infrared reflective coating on energy con-sumption of factory building in hot summer and warm winter zone. It first resorted to theoretical calculation, which demonstrated the beneficial effects of infrared reflective coating on reducing building energy consumption. Then it analyzed a field measurement done on two identical rooms respectively with ordinary coated roof and in-frared reflective coated roof from November 2006 to October 2007, on a 24h basis. The measured data include exterior and interior roof surface temperature, indoor air temperature, and indoor globe temperature. The relat-ed weather data is from a weather station near the measured area. The continuous measurement has been accom-plished in southern China, and the measured data indicate that roof surface temperature and heat gain are signifi-cantly decreased in summer while slight negative effects in winter are induced by adopting infrared reflective coating. Thus it is simple and applicable to reduce building energy consumption in this area by applying infrared reflective coating. Regress equation between reduced roof thermal property, such as surface temperature and heat gain, and reduction in absorbed solar radiation shows their highly linear relationship. Based on the mea-sured data, it is estimated that the reduced power consumption is 3.45 kWh/m2·month in June.  相似文献   
123.
The 6 major ENSO events since 1979 are classified into the strong and moderate ENSO based on intensity. The composite analysis is performed to reveal the influence of ENSO on East Asian summer monsoon (EASM) and summer rainfall in eastern China. It is shown that the influence is changed with the seasonal cycle in summer, with a weaker influence in June and a stronger influence in August, indicating a long lagged effect of ENSO on EASM. Besides, the circulation and rainfall anomalies caused by the strong ENSO are also stronger with an earlier starting time, while the influence of the moderate ENSO is evident in August. The composite summer rainfall in eastern China for the moderate ENSO exhibits a northern rainfall pattern, which is totally different from the classical ENSO-type rainfall pattern. Based on the composite analysis, two moderate ENSO years with a similar intensity (i.e., 1995 and 2003) are compared. The result shows that, the response of EASM to the moderate ENSO during June and July is, to a certain degree, modulated by the circulation systems in mid-high latitudes of Eurasia and in the Southern Hemisphere, thereby inducing a different rainfall distribution in eastern China. In comparison with the strong ENSO in 1983, it is further revealed that, the strong ENSO plays a dominant role in summer rainfall anomalies in eastern China as well as in controlling the influence of the other factors on EASM. The strong ENSO is therefore different with the moderate ENSO.  相似文献   
124.
以长江中游夏季1998年特大洪涝和2000年异常干旱为实例,对500hPa月平均高度场,极涡,阻塞高压,西太平洋副热带高压强度,面积指数等因子,进行同期大气环流特征对比分析,结果表明,1998年和2000年夏季东亚地区从北到南大气环流具有显著差异。  相似文献   
125.
1905~1990年徐州夏季气温资料表明,本世纪50年代后期凉夏出现频率呈上升趋势,至80年代后期又出现下降趋势。探讨这种气候变化趋势的特点及其成因,并对其未来发展作出预测。  相似文献   
126.
以大白鼠作为实验动物,在春分、夏至、秋分、冬至四节气中,分别观察了脑电图、心电图和心率的变化。实验结果表明,在四节气中,脑电图和心电图的变化节律,基本遵循着中医学认为的人体生理活动与四时的关系即“和于阴阳、调于四时”。  相似文献   
127.
A new approach to forecast the middle-lower reaches of the Yangtze River Valley summer rainfall in June-August (JJA) is proposed in this paper. The year-to-year increment of the middle-lower reaches of the Yangtze River Valley is forecasted and hence the summer precipitation could be predicted. In this paper, DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). YR denotes the seasonal mean precipitation rate of the middle-lower reaches of the Yangtze River Valley summer rainfall. After analyzing the atmospheric circulation anomalies in winter and spring that were associated with the DY of YR, six key predictors for the DY of YR have been identified. Then the forecast model for the DY of YR is established by using the multi-linear regression method. The predictors for the DY of YR are Antarctic Oscillation, the meridional wind shear between 850hPa and 200hPa over the Indo-Australian region, and so on. The prediction model shows a high skill for the hindcast during 1997-2006, with the average relative root mean square error is at 18%. The model can even reproduce the upward and downward trends of YR during 1984--1998 and 1998--2006. Considering that the current operational forecast models of the summer precipitation over the China region have the average forecast scores at 60%--70% and that the prediction skill for the middle-lower reaches of Yangtze River Valley summer precipitation remains quite limited up to now, thus this new approach to predict the year-to-year increment of the summer precipitation over the Yangtze River Valley (and hence the summer precipitation itself) has the potential to significantly increase the operational forecast skill of the summer precipitation.  相似文献   
128.
目的 为定量分析城市滨水带状绿地不同下垫面温湿度调节效应,选取安庆滨水带状绿地江滩公园为研究 对象,分析不同下垫面与降温增湿强度之间的关系,旨在为城市滨水带状绿地规划提供理论依据。 方法 于天气晴 朗夏季,选取 6 种下垫面(草地、乔草、乔灌草、水体、硬质铺装、建筑)为研究对象,以开阔的无植被区域作为对照, 测定温度、相对湿度、风速,比较不同下垫面之间降温增湿作用的差异。 结果 6 种下垫面均具有降温增湿作用,温 度日变化呈现出“单峰型”变化规律,湿度日变化呈现出 U 型变化,且各类型下垫面均在中午 11 ∶ 00—13 ∶ 00 达到 高温低湿状态,其中乔灌草与乔草两种下垫面与对照点之间的温湿度差异显著,水体与对照点之间的湿度差异极 显著,温度差异不显著,草地、硬质铺装、建筑与对照点之间的温湿度差异均不显著。 此外,不同类型林地中常绿阔 叶林降温增湿作用最为明显。 结论 不同类型下垫面表现出不同的调节作用,植物群落与水体能有效改善周边环 境小气候,该结果对合理配置滨水带状绿地植物具有实践指导意义。  相似文献   
129.
以温湿度独立控制空调系统作为研究对象,建立了不同形式温湿度独立控制空调系统模型.通过一实际工程对各系统的COP进行分析、计算,揭示了不同温湿度独立控制系统自身的性能和地区差异.通过对比发现,在室外空气含湿量相对较小的地区应优先考虑热泵转轮除湿系统,对于室外含湿量相对较大的地区适合选择溶液除湿系统和冷凝除湿系统.  相似文献   
130.
研究了修理工带有单重休假的n中取k(G)冷储备可修系统.假定部件寿命服从指数分布,修理时间和休假时间都服从一般分布且修复如新,利用补充变量方法和拉普拉斯变换工具,讨论了此系统的首次故障前平均时间,可用度及(0,t]时间内的平均故障次数等可靠性指标.结果表明,本文讨论的模型比以往的模型更具-般性.  相似文献   
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