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排序方式: 共有1681条查询结果,搜索用时 125 毫秒
1.
基于网络零售平台与制造商的合作广告实践,运用Stackelberg博弈理论研究了平台交叉销售效应及合作广告引导作用对O2O供应链合作广告决策的影响,并通过数值算例对参与合作广告计划前后渠道成员的决策变量均衡结果和利润进行对比分析,研究发现平台交叉销售效应是影响网络零售平台合作广告计划制定和实施的关键因素,只有当其达到一定水平时,制造商才拥有参与网络零售平台合作广告计划的资格;在一定条件时,合作广告计划能够实现制造商和网络零售平台利润的提升;当平台交叉销售效应较大时,网络零售平台获得的利润大于制造商。 相似文献
2.
"户外重厨房项目"是一种源于美国科拉多大峡谷大河漂流旅游的营地厨房服务模式,其特点是以物资为基础有效降低户外运动旅行的不舒适性,从而提高参与者评价度,促进旅游者消费。该项目需要在专业建设中囊括体育、旅游相关产业的旅游院校参加,提供一条"旅游+体育+餐饮+酒管"专业人才培养模式,培养复合型旅游人才,以有利于产业的全面、可持续发展以及体育旅游服务质量的提升。 相似文献
3.
Firebrand production from structure combustion becomes a key factor in the magnitude of how quickly a large outdoor fire may spread. Post‐fire disaster investigations suggest that attached building components, such as wood fencing assemblies are known to be prone to ignition in these fires, and may provide pathways to structure ignition. Here, a comparison of ignition results from full‐scale fencing assembly experiments conducted using a full‐scale wind tunnel facility, to mock‐ups of full‐scale fencing assemblies using the recently developed experimental capability at the National Research Institute of Fire and Disaster (NRIFD) are discussed. In both experimental facilities, the fencing assemblies were exposed to firebrand showers using custom built continuous feed firebrand generators with size and mass distributions similar to those generated from structure combustion. Similar ignition behaviors were observed between the full‐scale fencing assemblies and the mock‐up of full‐scale fencing assemblies. Additional experiments are required for other fencing assembly types to further verify these important findings. 相似文献
4.
Due to the severe outdoor PM2.5 pollution in China, many people have installed air-cleaning systems in homes. To make the systems run automatically and intelligently, we developed a recurrent neural network (RNN) that uses historical data to predict the future indoor PM2.5 concentration. The RNN architecture includes an autoencoder and a recurrent part. We used data measured in an apartment over the course of an entire year to train and test the RNN. The data include indoor/outdoor PM2.5 concentration, environmental parameters and time of day. By comparing three different input strategies, we found that a strategy employing historical PM2.5 and time of day as inputs performed best. With this strategy, the model can be applied to predict the relatively stable trend of indoor PM2.5 concentration in advance. When the input length is 2 h and the prediction horizon is 30 min, the median prediction error is 8.3 µg/m3 for the whole test set. For times with indoor PM2.5 concentrations between (20,50] µg/m3 and (50,100] µg/m3, the median prediction error is 8.3 and 9.2 µg/m3, respectively. The low prediction error between the ground-truth and predicted values shows that the RNN can predict indoor PM2.5 concentrations with satisfactory performance. 相似文献
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Junyao Li Weiqi Xu Zhijie Li Minzheng Duan Bin Ouyang Shan Zhou Lu Lei Yao He Jiaxing Sun Zifa Wang Lin Du Yele Sun 《Indoor air》2021,31(5):1364-1376
Most of human exposure to atmospheric pollutants occurs indoors, and the components of outdoor aerosols may have been changed in the way before reaching indoor spaces. Here we conducted real-time online measurements of mass concentrations and chemical composition of black carbon and the non-refractory species in PM2.5 in an occupied office for approximately one month. The open-close windows and controlled dampness experiments were also performed. Our results show that indoor aerosol species primarily originate from outdoors with indoor/outdoor ratio of these species typically less than unity except for certain organic aerosol (OA) factors. All aerosol species went through filtration upon transport indoors. Ammonium nitrate and fossil fuel OA underwent evaporation or particle-to-gas partitioning, while less oxidized secondary OA (SOA) underwent secondary formation and cooking OA might have indoor sources. With higher particulate matter (PM) mass concentration outdoors than in the office, elevated natural ventilation increased PM exposure indoors and this increased exposure was prolonged when outdoor PM was scavenged. We found that increasing humidity in the office led to higher indoor PM mass concentration particularly more oxidized SOA. Overall, our results highlight that indoor exposure of occupants is substantially different from outdoor in terms of mass concentrations and chemical species. 相似文献
8.
Jin Pan Julian Tang Miguela Caniza Jean-Michel Heraud Evelyn Koay Hong Kai Lee Chun Kiat Lee Yuguo Li Alejandra Nava Ruiz Carlos Francisco Santillan-Salas Linsey C. Marr 《Indoor air》2021,31(6):2281-2295
The incidence of several respiratory viral infections has been shown to be related to climate. Because humans spend most of their time indoors, measures of indoor climate, rather than outdoor climate, may be better predictors of disease incidence and transmission. Therefore, understanding the relationship between indoor and outdoor climate will help illuminate their influence on the seasonality of diseases caused by respiratory viruses. Indoor-outdoor relationships between temperature and humidity have been documented in temperate regions, but little information is available for tropical regions, where seasonal patterns of respiratory viral diseases differ. We have examined indoor-outdoor correlations of temperature, relative humidity (RH), and absolute humidity (AH) over a 1-year period in each of seven tropical cities. Across all cities, the average monthly indoor temperature was 25 ± 3°C (mean ± standard deviation) with a range of 20–30°C. The average monthly indoor RH was 66 ± 9% with a range of 50–78%, and the average monthly indoor AH was 15 ± 3 g/m3 with a range of 10–23 g/m3. Indoor AH and RH were linearly correlated with outdoor AH when the air conditioning (AC) was off, suggesting that outdoor AH may be a good proxy of indoor humidity in the absence of AC. All indoor measurements were more strongly correlated with outdoor measurements as distance from the equator increased. Such correlations were weaker during the wet season, especially when AC was in operation. These correlations will provide insight for assessing the seasonality of respiratory viral infections using outdoor climate data, which is more widely available than indoor data, even though transmission of these diseases mainly occurs indoors. 相似文献
9.
冷凝器是空调室外机中的重要零部件,根据其结构形式的不同可分为多种不同的类型。商用空调中常用类型为翅片管式冷凝器,它在不同类型的空调室外机中有不同的布局和结构。本文重点分析商用顶出风空调室外机中冷凝器的布局和设计。 相似文献
10.
节能建筑冬季供暖临界温度 总被引:2,自引:1,他引:2
给出了节能建筑供暖临界温度的计算方法,讨论了日照、建筑节能设计的影响,说明日照率低的地区供暖临界温度偏高,日照率高的地区增大南向窗墙比有利于建筑节能。 相似文献