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排序方式: 共有1402条查询结果,搜索用时 15 毫秒
61.
基于ARM的嵌入式Web服务器设计 总被引:2,自引:0,他引:2
将嵌入式技术与Web技术相结合,已成为目前嵌入式系统的一个重要发展方向和必然趋势。利用源代码开放的uClinux为操作系统平台,实现了以ARM微处理器为核心的嵌入式Web服务器,在分析了嵌入式Web服务器的体系结构后,给出了系统的硬件结构组成和软件设计。对Web服务器的测试结果表明,该服务器运行稳定、控制方便,将在智能家居、远程数据采集、工业控制等领域有着广泛的应用前景。 相似文献
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朱维 《重庆理工大学学报(自然科学版)》2006,20(6):112-114
象征主义作为新兴的文学思潮,在现代文坛上引起极大的争论。作为对现代中国的文学秩序的总结,这一时期的“文学概论”著作对象征主义等现代主义文学思潮的兴起、宣传和引导有十分重要的意义。“象征主义”从最开始被提上文学理论史的日程并被合理定位,到后来被边缘化的历程,是以国家和民族的现代化取代了现代文学之家的个性的历程,也是中国古代文学与文化的传统性和现代马列主义大一统化的历程。 相似文献
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This study drew on existing research and three behavioral intention models to develop the beginning of a new model to explain why college students share their locations on Facebook. Findings showed that students were more likely to disclose their location on Facebook if their friends did so, a concept called subjective norm. Results also showed that subjective norm had an indirect effect on whether people disclosed their location, mediated through people’s attitude toward disclosure, while controlling for usefulness of disclosing. Collectively, this model explained 61% of the variance in why college students share locations on Facebook. Findings are discussed in relation to behavioral-intention models, and practical implications for social media companies are offered. 相似文献
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The aim of this study was to prevent the delamination of encapsulant for light-emitting diode (LED) without sacrificing other optical performance. Silicone microsphere was employed to control the properties of shrinkage and hardness of encapsulant during curing process. The effects of microsphere in encapsulant were investigated by using the different concentration of microsphere. After curing reaction, the shrinkage percentage and hardness of both shore A and D encapsulants were reduced and reinforced, as increasing the concentration of microsphere. Despite the addition of microsphere, the LED packages fabricated without/with microsphere showed the similar initial optical efficiencies. It is because the light scattering effect compensated their small difference of refractive indexes between encapsulants and microsphere. Using the silicone microsphere, the improvement of reliability of LED packages could be achieved after 1000 h under condition of temperature (85 °C)/humidity (RH 85%). It is attributed to the synergy effects of shrinkage suppression and hardness improvement. 相似文献
68.
Dynamic crop models usually have a complex structure and a large number of parameters. Those parameter values usually cannot be directly measured, and they vary with crop cultivars, environmental conditions and managements. Thus, parameter estimation and model calibration are always difficult issues for crop models. Therefore, the quantification of parameter sensitivity and the identification of influential parameters are very important and useful. In this work, late-season rice was simulated with meteorological data in Nanchang, China. Furthermore, we conducted a sensitivity analysis of 20 selected parameters in ORYZA_V3 using the Extended FAST method. We presented the sensitivity results for four model outputs (LAI, WAGT, WST and WSO) at four development stages and the results for yield. Meanwhile, we compared the differences among the sensitivity results for the model outputs simulated in cold, normal and hot years. The uncertainty of output variables derived from parameter variation and weather conditions were also quantified. We found that the development rates, RGRLMN and FLV0.5 had strong effects on all model outputs in all conditions, and parameters WGRMX and SPGF had relative high effects on yield in cold year. Only LAI was sensitive to ASLA. Those influential parameters had unequal effects on different outputs, and they had different effects at four development stages. With the interaction effects of parameter variation and different weather conditions, the uncertainty of model outputs varied significantly. However, the weather conditions had negligible effects on the identification of influential parameters, although they had slight effects on the ranks of the parameters' sensitivity for outputs in the panicle-formation phase and the grain-filling phase, including yield at maturity. The results suggested that the influential parameters should be recalibrated in priority and fine-tuned with higher accuracy during model calibration. 相似文献
69.
《International Journal of Hydrogen Energy》2019,44(12):6103-6115
In this contribution, we reported the preparation of a novel conducting polymer hydrogel (CPH) by a sol-gel method, which was subsequently employed to fabricate a flexible all-solid-state supercapacitor device. Taking advantage of the synergistic effects of the different components in the conducting polymer hydrogel and the merits of the proposed synthesis strategies, the prepared supercapacitor device with CPH as electrode exhibited high area-normalized capacitance (2.2 F cm−2), high gravimetric capacitance (1573.6 F g−1) as well as high energy density of 0.18 mWh cm−2 (or 128.7 Wh Kg−1) at 0.08 mW cm−2 (or 55.1 W kg−1). This study did not only represent a novel all-solid-state, high performance, flexible supercapacitor with potential applications in flexible energy-related devices, but also developed a new method for enhancing capacitances and mechanical stability of all-solid-state flexible supercapacitor. 相似文献
70.
《International Journal of Hydrogen Energy》2019,44(43):23936-23946
Construction of transition metal selenides with high electrocatalytic performance is of significant importance, but it is still a challenge to develop the corresponding counter electrodes (CEs) by an electrodeposition technique. In the present work, nickel cobalt selenide (NixCoySe) films are prepared in situ on fluorine-doped tin oxide (FTO) glasses through a potential reversal electrodeposition technique. The morphology and electronic structure of NixCoySe films can be tuned by controlling the Ni/Co molar ratio in electroplating solution. Specially, NixCoySe-6 film (the Ni/Co molar ratio of 1:1) with the optimized interaction between the Ni and Co elements displays numerous particles composed of sheets attached with nanocrystals, resulting in the more electrocatalytic active sites. Benefiting from the unique morphology and optimized synergistic effect, NixCoySe-6 CE exhibits superior electrocatalytic activity for the triiodide reduction. Then, the dye-sensitized solar cell (DSC) fabricated by NixCoySe-6 CE has demonstrated a power conversion efficiency (PCE) over 7.40%, which is higher than that of platinum (Pt)-based device (6.32%). Furthermore, NixCoySe-6 array CE is also prepared by using polystyrene array as template. The PCE of the DSC with NixCoySe-6 array CE reaches its maximum value of 7.64% and 20.9% larger than that of Pt-based device. 相似文献