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张茜 《四川烹饪高等专科学校学报》2014,(3):4-8
餐饮企业是中国传统岁时节日食俗在当代有效传承的重要场所和平台之一。文章探讨了研究中国传统岁时食俗在餐饮业应用的积极意义,梳理和总结了中国传统岁时食俗在餐饮业应用的历史和现状,并提出了餐饮业应用中国传统岁时食俗的对策,即以合适的品种为中心、倡导大众餐饮,以成功的经验为基础、加强宣传和营销等,以更好弘扬中国传统文化,促进中国餐饮业的发展。 相似文献
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本文以雪峰山观冰站2006~2013年冬季的覆冰观测成果为样本资料,运用GrADS软件对再分析气象资料NECP做数据读取与加工计算,统计出雪峰山区域的逆温日数和分布特性,根据雪峰山站实测资料,统计出样本资料的结冰日数,结合再分析资料的计算结果,对雪峰山站结冰日数与逆温日数做概率统计分析,建立结冰日数与逆温日数之间的条件概率关系,获得了结冰日数的一般公式与雪峰山结冰日数的经验公式,选择湖南雪峰山站、四川罗汉林站、贵州大新寨点的覆冰观测资料为验证样本,运用结冰日数经验公式计算各站点的结冰日数,其结果与实际观测结冰日数误差范围为0~0.8天,结冰日数公式具有一定的适用性。 相似文献
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岩溶区面临严峻的水资源形势,为解释云南省岩溶区近60年来降水的历史变化特征并服务现今的水资源管理,以云南省5个岩溶片区1959-2017年的逐日降水量数据为基础,采用线性倾向估计法和Mann-Kendall非秩次检验法,系统性研究了云南岩溶区降水变化特征。结果表明:自1959年以来,云南省5个岩溶片区的降水量均呈现出减少的趋势,其中滇中和滇东南的减少最为明显,但均未达到0. 05的显著性水平;云南岩溶区降水日数均呈现出减少的倾向,其中滇西、滇中、滇东南片区的减少趋势达到0. 05置信水平,其余区域不明显;小降水级别的降水量在云南岩溶区呈减少态势,而大降水级别的降水量则有所增加; 5个岩溶区多年平均最长干旱时间的变化存在较大的区域差异,其中滇西北、滇西、滇东北和滇东南片区的最长持续干旱时间均有所增加,而滇中则呈现为减少趋势;云南5个岩溶片区的平均最长持续降水时间均呈现出减少趋势,其中滇东北片区的减少趋势变化显著。降水的这些变化趋势给岩溶区水资源利用与生态环境保护提出了新的挑战。 相似文献
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地闪参量特征的统计分析 总被引:12,自引:10,他引:2
通过对北京和兰州中川地区测到的地闪资料进行的计算和统计分析,总结了两地区正负地闪的电流幅值、电流梯度、回收数、峰值电流时间、回周间隔等一批在防雷工程中具有较大在参考价值的闪电参量的概率分布特征,以及北京地区的平均年落雷密度分布和平均年雷暴日分布。 相似文献
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Estimation of net radiation from the MODIS data under all sky conditions: Southern Great Plains case study 总被引:4,自引:0,他引:4
Net radiation is a key component in the surface radiation budget. Numerous studies have developed frameworks to estimate net radiation or its components (upwelling or downwelling longwave and/or shortwave radiation) from remote sensing data for clear sky conditions. Application of existing methodologies to estimate net radiation for cloudy sky conditions from remote sensing sensors remains a significant challenge. In this paper, we present a framework to estimate instantaneous and daily average net radiation under all sky conditions from using the data from the MODerate Resolution Imaging Spectroradiometer (MODIS), onboard from the Terra satellites. Bisht et al. (2005) methodology is used for the clear sky portion of the MODIS overpass; while for cloudy portion of the MODIS overpass an extension of Bisht et al. (2005) methodology is applied. The extension of Bisht et al. (2005) methodology utilizes the MODIS cloud data product (MOD06_L2) for cloud top temperature, cloud fraction, cloud emissivity, cloud optical thickness and land surface temperature for cloudy days. The methodology is applied over the Southern Great Plains (SGP) for a time period covering all seasons of 2006. During the MODIS-Terra overpasses in 2006 over the SGP, only 24% of day-overpasses and 9% of night-overpasses had 75% or more of the study region as cloud free. Thus, this proposed study is applicable to a large portion of the MODIS-Terra overpasses. The root mean square errors (RMSE) of instantaneous and daily average net radiation estimated under cloudy conditions using the MOD06_L2 product, comparing to ground-based measurements are 37 W m− 2 and 38 W m− 2, respectively. The strength of the proposed methodology is that it can rely exclusively on remote sensing data in the absence of ancillary ground observations, thus it has a potential to estimate surface energy budget globally. 相似文献
37.
针对短期电力负荷预测精度低、泛化能力弱等问题,提出了一种基于相似日选取与多集成组合的短期电力负荷预测模型.首先利用最大信息准则MIC(maximal information coefficient)选取高相关变量作为模型输入;然后综合考虑MIC与灰色关联度,对气象敏感性较弱地区的负荷进行相似日选取;最后引入集成随机子空... 相似文献
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Lowering the outdoor temperature in high-rise high-density residential developments of coastal Hong Kong: The vegetation influence 总被引:2,自引:0,他引:2
This paper investigates the impact of on-site variables on the influence of vegetation in lowering outdoor temperature. The study uses six critical on-site variables such as surface albedo, sky view factor, altitude, shrub cover, tree cover and average height to floor area ratio to carry out analysis in five data sets. The climatic parameters and physical characteristics were measured and surveyed, respectively in 216 stations in high-rise high-density residential developments of coastal Hong Kong. The data set is mainly categorised into peak summer clear sky days (PSCS-days), peak summer partially cloudy days (PSPC-days) and late summer days to address the issues related to cloudy sky conditions in Hong Kong. The trend analysis shows that at a lower sky view factor, ranging from 0.1 to 0.25, shrub cover as low as 10–15% in a 1000 m2 open area is more effective in reducing outdoor temperature than the same level of tree cover in a location with a higher sky view factor (0.4 or above). The regression models used in this study were able to explain the influence of on-site variables on vegetation in lowering the outdoor temperature within the respective urban settings. In high-rise high-density environments, on-site variables such as sky view factor and altitude have a substantial impact on the influence of vegetation in lowering outdoor temperature. However, off-site variables such as high urban density and anthropogenic heat could negate the behaviour of sky view factor and altitude. The study suggests that increasing the tree cover from 25% to 40% in the pocket parks in coastal area residential developments of Hong Kong could reduce daytime urban heat island intensity (UHI) by further 0.5 °C. 相似文献