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81.
Transitioning to more efficient and less carbon-intensive heating is a monumental policy challenge in the United Kingdom. However, very few households in the UK—and perhaps even elsewhere—have actual experience with state-of-the-art smart heating systems that may utilize enhanced control or feedback. Drawing from a unique sample of actual adopters of smart heating, this study closely examines the heating preferences, practices, and profiles of homes when they are given smarter heating systems. The study utilizes qualitative household data from the Energy System Catapult’s Living Laboratory of 100 smart homes in Birmingham (West Midlands), Bridgend (Wales), Manchester (Greater Manchester), and Newcastle (Northumberland). We examine the heating preferences and profiles of participants, with findings inductively organized around the themes of temperature, including tradeoffs between comfort, cost, and value; time, including the utility of heat scheduling; and space, including zonal heating controls. We also discuss patterns of learning, the emergence of environmental values, and issues of discomfort. We conclude by commenting on important distinctions between radiant and ambient heat, as well as between scheduled and on-demand heat. The main findings are 1) tradeoffs between comfort, value and cost occur when it comes to smart heating; 2) people want different numbers of warm hours in their homes at very different times; 3) households chose to heat different numbers of rooms; and 4) there are other non-monetary and non-functional aspects of smart heating that households value. 相似文献
82.
针对现有人工混响方法中反馈延迟网络方法存在延迟线的个数选择受限和无法设定子带混响时间的不足,本文设计了一种基于Householder反馈矩阵和Butterworth滤波器组的反馈延迟网络人工混响器.Householder反馈矩阵有助于最大化回声密度,延迟线个数的选择相对自由,Butterworth滤波器组便于设定子带混响时间.仿真实验中分别利用语谱图、语音质量感知评价和主观评价验证了本文方法的有效性. 相似文献
83.
AbstractSatellite observations revealed that there is a close relationship between perturbations of sea surface temperature (SST) and wind stress (τ) induced by tropical instability waves (TIWs; SSTTIW and τ TIW). Using the empirical relationship observed between TIW-induced wind stress divergence (curl) and downwind (crosswind) SST gradients, this study establishes a TIW-induced wind stress field perturbation model τ TIW?=?F(SST). This empirical model solves τ TIW from the TIW-induced wind stress divergence and curl, which are estimated from the downwind and crosswind SST gradients. This empirical τ TIW?=?F(SST) model can be incorporated into the ocean model to take into account the effect of τ TIW. By comparing two experiments with and without the τ TIW effect, this study demonstrates that τ TIW has a substantial effect on the equatorial Pacific heat budget and induces the long-term mean SST to exhibit a 0.2°C difference, which is consistent with previous studies. 相似文献
84.
The nature of the reduction trend and quasi-decadal oscillation in Northern Hemisphere sea-ice extent is investigated. The trend and oscillation that seem to be two separate phenomena have been found in data. This study examines a hypothesis that the Arctic sea-ice reduction trend in the last three decades amplified the quasi-decadal Arctic sea-ice oscillation (ASIO) due to a positive ice/ocean-albedo feedback, based on data analysis and a conceptual model proposed by Ikeda et al. The theoretical, conceptual model predicts that the quasi-decadal oscillation is amplified by the thinning sea-ice, leading to the ASIO, which is driven by the strong positive feedback between the atmosphere and ice-ocean systems. Such oscillation is predicted to be out-of-phase between the Arctic Basin and the Nordic Seas with a phase difference of 3/4, with the Nordic Seas leading the Arctic. The wavelet analysis of the sea ice data reveals that the quasi-decadal ASIO occurred actively since the 1970s following the trend starting in the 1960s (i.e., as sea-ice became thinner and thinner), as the atmosphere experienced quasi-decadal oscillations during the last century. The wavelet analysis also confirms the prediction of such out-of-phase feature between these two basins, which varied from 0.62 in 1960 to 0.25 in 1995. Furthermore, a coupled ice-ocean general circulation model (GCM) was used to simulate two scenarios, one without the greenhouse gas warming and the other having realistic atmospheric forcing along with the warming that leads to sea-ice reduction trend. The quasi-decadal ASIO is excited in the latter case compared to the no-warming case. The wavelet analyses of the simulated ice volume were also conducted to derive decadal ASIO and similar phase relationship between the Arctic Ocean and the Nordic Seas. An independent data source was used to confirm such decadal oscillation in the upper layer (or freshwater) thickness, which is consistent with the model simulation. A modified feedback loop for the sea-ice trend and ASIO was proposed based on the previous one by Mysak and Venegas and the ice/albedo and cloud/albedo feedabcks, which are responsible for the sea ice reduction trend. 相似文献
85.
Peter A. Rogerson 《The Professional geographer》1984,36(3):307-314
Although the recent growth in the nonmetropolitan population of the U.S. is now well documented, little attention has been given to the consequences these trends will have on the future composition and growth of metropolitan and nonmetropolitan regions. This paper discusses the feedback effects of migration on the future age structure and population growth of both regions during the period 1975–2000. 相似文献
86.
利用各频率观测值间物理上的相关性,采用数学变换得到一个含有双频原始载波观测信息的虚拟观测值,与双频数据按长波长特性进行多频组合来放大周跳。对探测出的周跳候选值利用Melbourne-Wubbena组合及多项式拟合作为两个判别条件来进行甄选,达到了实时修复双频原始载波相位观测值周跳的目的。 相似文献
87.
基于新的区域电离层模型SEID,结合大范围近实时气象反演的特点对该模型构建方法进行了一定发展,提出了一套基于双频参考站网的GNSS单频接收机大范围近实时气象监测网解数据处理策略,并利用山西CORS网及周边多个IGS站连续一周的实测数据,对在不同范围参考网内应用该策略实现单频接收机近实时气象反演的精度和可行性进行了验证分析。实验结果表明,对于山西省内249km以下的参考网,利用网内单频接收机能够满足区域近实时1~2mm精度PWV的反演要求。 相似文献
88.
结合RTK技术及其特点,论述了RTK直线放样功能应用于地质勘查测量中的重要性,并通过非洲工程实例,得出RTK技术具有广阔的应用前景的结论. 相似文献
89.
90.