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In this paper, a new energy management algorithm has been suggested for the ships connected with alternative energies considering the smart electricity grid features. The algorithm focuses on the use of optimum energy source on the shipboard based on the priorities of authorities such as the most economic, environmental, or both criteria at the ports. The algorithm is performed in MATLAB, and several case studies are simulated to validate the results. The 5 maritime nations, which are at different regions: United States, Belgium, Turkey, China, and Australia, are taken into account in the case studies. The actual data of a bulk carrier ship have been used to achieve tangible results in the simulations. The results of the case studies are compared to determine the changes of energy cost and released emission to meet demand of electricity on the ships. Capital cost of the proposed concept is also given to make an economic evaluation. The results show that the ship energy management algorithm provides the significant economic and environmental advantages. This paper aims to contribute to the importance of the ships in the smart electricity grid concept for the maritime and electricity sector representatives. 相似文献
43.
Gizem Yanalak Abdalaziz Aljabour Emre Aslan Faruk Ozel Imren Hatay Patir 《International Journal of Hydrogen Energy》2018,43(36):17185-17194
The efficiencies of a series of hydrogen evolving catalysts based on metal oxide nanofibers (NiO, Co3O4, Mn3O4) are investigated for the photocatalytic hydrogen evolution from water without using any co-catalyst under the visible light irradiation by using triethanolamine (TEOA) as an electron donor and Eosin-Y (EY) dye as a photosensitizer. It is found that the photocatalytic hydrogen evolution activities follow the order as: Mn3O4<Co3O4<NiO (196 μmolg?1h?1, 5552 μmolg?1h?1, 7757 μmolg?1h?1, respectively). Moreover, the catalytic behavior of these nanofibers on the hydrogen production has been also compared to bulk forms of NiO, Co3O4 and Mn3O4 by producing hydrogen 937 μmolg?1h?1, 901 μmolg?1h?1 and 135 μmolg?1h?1, respectively. The nanofiber structures demonstrated much higher photocatalytic activity than bulk forms due to the effect of the increased surface to volume ratio deduced from the fibrous character. The photocatalytic plausible pathway for the hydrogen production is also discussed. 相似文献
44.
该文以在工程检测中大量抽取搅拌桩水泥土芯样的无侧限抗压强度的实际数据为基础 ,从正确理解文献 [2 ]折减系数与水泥土安全分项系数和搅拌桩安全分项系数的关系 ,提出如何理解搅拌桩的设计意图 ,从而对利用搅拌桩芯样的无侧限抗压强度来判断深层搅拌桩的质量提出了看法 ,并对如何设计深层搅拌桩提出了建议 相似文献
45.
本文提出一种新型水泥工业余热与生物质能互补发电系统,该系统采用水泥窑低温余热和生物质补燃有机结合的方式大幅提高水泥窑余热发电蒸汽参数与系统效率。来自水泥生产线窑头和窑尾的低温余热烟气全部用来加热工质水产生饱和蒸汽,饱和蒸汽进入生物质补燃系统中进行过热后送入汽轮发电机组中做功发电,补燃燃料为生物质气化燃气。本研究建立了单压和双压2种互补发电系统,分析了其热力学性能,结果表明:单压互补发电系统与传统单压纯低温发电系统相比,系统循环热效率和系统发电效率分别提高了1.63和1.92个百分点。双压互补发电系统与传统双压纯低温发电系统相比,系统循环热效率和系统发电效率分别提高了1.05和1.53个百分点。 相似文献
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Emel Ozel Hilmi Yurdakul Servet Turan Matteo Ardit Giuseppe Cruciani Michele Dondi 《Journal of the European Ceramic Society》2010,30(16):3319-3329
Cobalt-doped willemite is a promising blue ceramic pigment, but some important aspects concerning crystal structure, optical properties and technological behaviour are still undisclosed. In order to get new insight on these features, willemite pigments (Zn2?xCoxSiO4, 0 < x < 0.3) were synthesized by the ceramic route and characterized from the structural (XRPD with Rietveld refinement), optical (DRS and colorimetry), microstructural (SEM, STEM, TEM, EDX, EELS) and technological (simulation of the ceramic process) viewpoints. The incorporation of cobalt in the willemite lattice, taking preferentially place in the Zn1 tetrahedral site, induces an increase of unit-cell parameters, metal–oxygen distances, and inter-tetrahedral tilting. It causes shifting and enhanced splitting of spin-allowed bands of Co2+ in tetrahedral coordination, implying slight changes of crystal field strength Dq and Racah B parameter, but increasing spin-orbit coupling parameter λ. Willemite pigments impart deep blue hue to ceramic glazes and glassy coatings with a colouring performance better than commercial Co-bearing colorants in the 800–1200 °C range. Detailed SEM-TEM investigation and microanalysis proved that no diffusion phenomena occur at the pigment–glassy coating interface and that willemite pigments are chemically inert during firing at 1050 °C. 相似文献
49.
电机电流分析法在机床类设备诊断中的应用研究 总被引:2,自引:0,他引:2
机床类设备传动链复杂,结构紧凑且封闭,对传动系统状态监测一直没有有效的分析办法,即使在噪声增大等恶劣情况下,常规的振动诊断方法也难以奏效.本文尝试用电流信号分析法,简称MCSA(Motor Current Signal Analysis),对机床状态进行测试和分析.通过电机电流信号的传动链齿轮谱特征分析,对其做出了正确评估,表明定子电流能很好地反映机床传动系统部件的运行状况.同时进行了多种运行工况的测试与试验,研究结论对机床类设备的生产制造和现场运行状态的分析提供了有效依据. 相似文献
50.
Comparison of total‐etch,self‐etch,and selective etching techniques on class V composite restorations prepared by
Er:YAG laser and bur: a scanning electron microscopy study 下载免费PDF全文
Emre Ozel Elif Bahar Tuna Sonmez Firatli Erhan Firatli 《Microscopy research and technique》2016,79(10):998-1004
The purpose of this study was to compare total‐etch, self‐etch, and selective etching techniques on the marginal microleakage of Class V composite restorations prepared by Er:YAG laser and bur. Class V cavities prepared on both buccal and lingual surfaces of 30 premolars by Er:YAG laser or bur and divided into six groups. The occlusal margins were in enamel, and the cervical margins were in cementum. Group‐1: bur preparation(bp)+Adper Single Bond 2 (ASB)+Filtek Z550 (FZ); Group‐2: laser preparation(lp)+(ASB)+(FZ); Group‐3: bp + Clearfil S3 Bond Plus (CSBP)+(FZ); Group‐4: lp+(CSBP) (FZ); Group‐5: bp + acid etching+(CSBP)+(FZ); Group‐6: lp + acid etching+(CSBP)+(FZ). All teeth were stored in distilled water at 37°C for 24 hr, and then thermocycled 1000 times (5–55°C). Five teeth from each group were chosen for the microleakage investigation, and two teeth for the scanning electron microscope evaluation. Teeth which were prepared for the microleakage test were immersed in .5% methylene blue dye for 24 hr. After immersion, the teeth were sectioned and observed under a stereomicroscope for dye penetration. Data were analyzed using Kruskal–Wallis and Mann–Whitney U tests (p < .05). More microleakage was observed in the cervical regions compared to the occlusal regions in Groups 3, 5, and 6, respectively (p < .05). There is no statistically significant difference in Groups 1, 2, and 4, in terms of cervical regions versus occlusal regions (p > .05). No significant differences were observed among any groups in terms of occlusal and cervical surfaces, separately (p > .05). Different etching techniques did not influence microleakage of Class V restorations prepared by Er:YAG laser and bur. 相似文献