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41.
42.
The high penetration of variable sources of renewable power generation will lead to operational difficulties in supply/demand balancing in the entire power system. The mass deployment of electric vehicles (EVs) and plug‐in hybrid vehicles (PHEVs) will also cause significant changes in electricity demand. Therefore, controlling and managing the charging time of EVs/PHEVs are effective approaches that are imperative for improving balancing in power system operation. We assumed travel patterns for EVs in a model of the future Tokyo power system and analyzed the power system loads, including the charging load of the EVs, under several charging control scenarios. We verified that charging time controls are substantially effective for reducing the fuel costs in the power system. Further, we found that load leveling under a multicar charging management scenario gave the best results in terms of the fuel costs in all cases.  相似文献   
43.
The objective of this study is to investigate the impact of biomass feeding location on rice husk gasification for hydrogen production. By comparing the results between top-feed and bottom-feed of the feedstock of the fluidized bed biomass gasification at the reaction temperature between 600~1000 °C and ER = 0.2, 0.27, and 0.33 without steam, the optimum low heating value was increase by 2.35 kJ/g-rice husk by the top-feed to gasifier. Although the yield of hydrogen was decreased by 42% for the rice husk gasification by the top-feed operation, the yield of CO, CO2, and CH4 were highly increased, which enhancing the heating value of the effluent gas. The study results suggested the potential route of the biomass gasification at the different feeding location.  相似文献   
44.
立捣卧挤炭素挤压机采用立式捣固预压,卧式挤压,旋转料室+延长料室结构,旋转料室和延伸料室均采用过盈配合,粗加工后要进行热装,压机整体高度较高,由于厂内不具备现场安装条件,导致装配难度很大,通过工艺和装配攻关,确定合理的安装方案,制作专用工装工具,采取相应措施,保证装配精度符合要求。  相似文献   
45.
To solve the problem that the existing acoustic emission (AE) source location algorithms cannot always obtain accurate results for multilayer cylindrical media, a new acoustic emission source location method considering refraction was proposed. AE source coordinates were solved by the complex method. Pencil-lead-break experiments were used to verify this method. The absolute distance errors of location results are less than 3 mm, much less than those by the traditional method. The numerical experiments were used to further analyze factors that affect location accuracy. The results of numerical experiments show that the location accuracy of the proposed method is not affected by the ratio of wave velocities but affected by the measurement accuracy of wave velocity. These results show that new method can obtain accurate AE source location in the two-layered cylindrical surface media such as the triaxial compression test.  相似文献   
46.
武徽  姚树楷 《煤矿机械》2020,41(3):26-28
针对当前装车站抛撒式卸料过程中,过程控制难度大、物料极易偏载、人工介入程度高等问题,开发设计了一种全自动抗偏载的抛撒式卸料系统。通过跟踪待卸载的物料状态和列车运动的情况,实现对溜槽卸料闸板的自动连续控制。该系统在抛撒式卸料情况下,可将物料均匀有序填充到车厢底部,避免了偏载情况的出现和人工干预的情况,提高了装车系统的自动化程度。  相似文献   
47.
This study aims to investigate the defensible character of the Lahore railway station built in response to “the war of independence in 1857,” which greatly impacted the location and design of the building. This study demonstrates the integral role played by the railway station in the development of the new colonial city, which the British wants to be defensive in every aspect. Railways were introduced in Pakistan (India) soon after their inauguration in Britain. Beginning from the mode of transportation, the multifaced contribution of railways toward the urban growth, new architectural style, mode of construction, and technology cannot be recanted. The research is based on the documentation and analysis of the history of Lahore railway station design. First, this study uses primary and secondary data to offer a history of the Lahore railway station from its inception to final execution. Second, it explores the criteria adopted by the British for its site selection to make the station a defensible post. The research finding includes the visual features that enhanced the architectural character of the building. Qualitative methods are used including several other approaches, namely, literature review, archival data collection, analysis of photographs, and study of architectural drawings and old maps, to achieve the objectives.  相似文献   
48.
区域自动气象站当中的设施设备是否可以正常、稳定运行,不仅会直接决定气象监测工作质量,同时还会形成严重的经济损失。对此,为了更好地保障气象监测工作质量,文章简要分析区域自动气象站常见故障及维修方法,希望可以为相关工作者提供理论帮助。  相似文献   
49.
BC系列粒状铵油炸药装药车是露天矿山机械化混药、装药设备,在矿山应用已有10年时间,给矿山带来了显著的经济效益和社会效益。本文对该系列装药车的应用实践作了简述,并对其应用情况提出了看法。  相似文献   
50.
On-site hydrogen production through steam-methane reforming (SMR) from city gas or natural gas is believed to be a cost-effective way for hydrogen-based infrastructure due to high cost of hydrogen transportation. In recent years, there have been a lot of on-site hydrogen fueling stations under design or construction in China. This study introduces current developments and technology prospects of skid-mounted SMR hydrogen generator. Also, technical solutions and economic analysis are discussed based on China's first on-site hydrogen fueling station project in Foshan. The cost of hydrogen product from skid-mounted SMR hydrogen generator is about 23 CNY/kg with 3.24 CNY/Nm3 natural gas. If hydrogen price is 60 CNY/kg, IRR of on-site hydrogen fueling station project reaches to 10.8%. While natural gas price fall to 2.3 CNY/Nm3, the hydrogen cost can be reduced to 18 CNY/kg, and IRR can be raised to 13.1%. The conclusion is that skid-mounted SMR technology has matured and is developing towards more compact and intelligent design, and will be a promising way for hydrogen fueling infrastructures in near future.  相似文献   
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