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排序方式: 共有3879条查询结果,搜索用时 31 毫秒
1.
Wassim Bahr 《国际自然能源杂志》2018,39(8):802-812
This paper assesses building integrated photovoltaic (BIPV) installation parameters based on the profit generated by a photovoltaic system. It takes into consideration a home building case study and it investigates its monthly energy demand based on a specific location and a typical occupancy. The capability of a photovoltaic (PV) system to generate more profit occurs when solar intensity is maximum while the electric energy price is at its highest rate. The paper traces a framework that encompasses different aspects such as energy demand, energy price, and solar intensity. This framework identifies profit alternatives according to different installation parameters. A tool that predicts a PV installation hourly electric energy production is developed. The profit generated is simulated for home buildings located in Beirut (Lebanon) and Xihua (China), both at 33.8° latitude north. The paper highlights a new approach for BIPV installations, taking into account weather conditions, energy demand, and electric energy utility rates. 相似文献
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Mining high utility itemsets (HUIs) from transaction databases considers such factors as the unit profit and quantity of purchased items. Two-phase tree-based algorithms transform a database into compressed tree structures and generate candidate patterns through a recursive pattern-growth procedure. This procedure requires a lot of memory and time to construct conditional pattern trees. To address this issue, this study employs two compressed tree structures, namely, Utility Count Tree and String Utility Tree, to enumerate valid patterns and thus promote fast utility computation. Furthermore, the study presents an algorithm called single-phase utility computation (SPUC) that leverages these two tree structures to mine HUIs in a single phase by incorporating novel pruning strategies. Experiments conducted on both real and synthetic datasets demonstrate the superior performance of SPUC compared with IHUP, UP-Growth, and UP-Growth+ algorithms. 相似文献
3.
Mizuki Tenjimbayashi Sadaki Samitsu Yuko Watanabe Yasuyuki Nakamura Masanobu Naito 《Advanced functional materials》2021,31(21):2010957
Liquid marble (LM) is a droplet that is wrapped by hydrophobic solid particles, which behave as a non-wetting soft solid. Based on these properties, LM can be applied in fluidics and soft device applications. A wide variety of functional particles have been synthesized to form functional LMs. However, the formation of multifunctional LMs by integrating several types of functional particles is challenging. Here, a general strategy for the flexible patterning of functional particles on droplet surfaces in a patchwork-like design is reported. It is shown that LMs can switch their macroscopic behavior between a stable and active state on super-repellent surfaces in situ by jamming/unjamming the surface particles. Active LMs hydrostatically coalesce to form a self-sorted particle pattern on the droplet surface. With the support of LM handling robotics, on-demand cyclic activation–manipulation–coalescence–stabilization protocols by LMs with different sizes and particle types result in the reliable design of multi-faced LMs. Based on this concept, a single bi-functional LM is designed from two mono-functional LMs as an advanced droplet carrier. 相似文献
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通过对有线电视系统干扰信号产生原因的理论分析,提出在实际操作中的解决方案,以期达到使有线电视系统信号的输出更稳定、电视画面更清晰的目的。 相似文献
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通过分析黄河口河道在纵剖面、横断面、河型等方面的演变过程,总结归纳出黄河口河道的演变规律。指出:黄河口泥沙在潮汐涨落等因素影响下,河口河道纵剖面逐渐形成台阶状,与此同时,河口滩地横比降逐渐发展为倒比降;河口河道中段由顺直型河道逐渐转为弯曲型河道,而下段仍为相对顺直、游荡型河道。当河口河道中段比降减小到一定程度后,此河段开始漫滩、卡冰、出汊。河口台阶的形成揭示了黄河口流路由单股河道逐渐转为出汊的过程,即黄河口流路由“青壮期”逐渐转为“衰亡期”的过程。延长黄河口流路使用年限的途径是:①尽量减少黄河下游输向黄河口的泥沙量;②采取河口挖沙或人工改汊措施,地点宜选在河口河道的中下段。 相似文献
7.
单脉冲导引头对多干扰源的角分辨 总被引:8,自引:0,他引:8
当多个噪声调频干扰同时进入单脉信号引头主波束内时,导引头对干扰源的角度分辨是非常困难的。本文主要研究了导引头单脉冲接收机对宽带噪声调频干扰源的响应,分析了当单脉冲主波束内存在多个噪声调频干扰源时,导引头指向角的跟踪规律,并重点讨论了一种用聚类来提取角信息的方法,最后仿真证实了该方法的正确性和有效性。 相似文献
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Results from applying the model on a sample of contractors, the majority of whom were international and operating in Egypt, reinforces the credibility of the developed methodology, claim the authors. 相似文献