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排序方式: 共有2873条查询结果,搜索用时 31 毫秒
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This paper investigates parameter identification of nonlinear Wiener-Hammerstein systems by using filter gain and novel cost function. Taking into account the system information is corrupted by noise, the filter gain is exploited to extract the system data. By using several auxiliary filtered variables, an extended estimation error vector is developed. Then, based on the discount term of the extended estimation error and the penalty term on the initial estimate, a novel cost function is developed to obtain the optimal parameter adaptive law. Compared with the conventional cost function which is composed of the square sum of output error, the proposed algorithm based on the cost function of this paper can provide faster convergence rate and higher estimation accuracy. Furthermore, the convergence analysis of the proposed scheme indicates that the parameter estimation error can converge to zero. The effectiveness and practicality of the proposed scheme are validated through the simulation example and experiment on the turntable servo system. 相似文献
3.
Elli Ntakou Ralph Masiello Farnaz Farzan Shay Bahramirad Aleksi Paaso M.A. Nayeem Maigha Maigha Daniel Kushner 《The Electricity Journal》2019,32(4):45-49
This paper presents part of the work ComEd and Quanta Technology have performed to quantify the locational and temporal value of DER to avoid distribution grid upgrade investments. It focuses on the formulation of a robust and efficient algorithm for DER optimal dispatch on a distribution feeder to mitigate the violation of current and voltage limits using the allocated cost of capacity and locational marginal value of real and reactive DER injection/withdrawal. 相似文献
4.
随着铜山口铜矿地下深部基建结束,坑道探矿存在安全事故隐患、地质取样质量无法保证的问题,为了加快生产探矿,发挥坑内钻优势,弥补坑道探矿不足,购置了3台坑内钻进行探矿。通过在主矿体生产探矿及周边扫盲增储、尖灭矿体探边摸底、零星小矿体追寻、超前探水、指导巷道掘进方向等应用,结果表明,坑内钻具有操作灵活机动,易掌握,缩短了生产探矿时间,节约探矿成本,作业现场安全等优势,保持了三级矿量的动态平衡,确保了生产持续稳产发展。 相似文献
5.
An integrated approach to measure the cost efficiency of the postal network of Universal Service Provider is proposed. An integrated approach enables the measurement of cost efficiency for delivery and non-delivery postal network units. The proposed approach is verified and tested on the postal network of the selected provider and the results were derived by using Data Envelopment Analysis (DEA). The results show that the main sources of inefficiency are inadequate allocation of resources relative to the network units. In addition, the study indicates that economies of scale have a positive impact on the efficiency of postal network units. 相似文献
6.
《International Journal of Hydrogen Energy》2020,45(27):13862-13875
Hydrogen has been a promising energy carrier to meet the world's energy needs as well as reduce pollutant emissions. Although many countries have policies and programs to expand hydrogen production, the potential for hydrogen production in different regions of Qatar has not yet been evaluated. Therefore, this paper, for the first time, evaluates the possibility of an average annual cogeneration of 14 kWh of electricity and 85 kg/day of hydrogen by a home-scale solar-wind system connected to the grid in Qatar. NASA's 20-year average of meteorological data, the electricity tariff and gasoline price in 2018, along with annual real interest rate, were used as inputs to HOMER software. The techno-econo-enviro analysis was done over a one-year period hour by hour. From the results, it was found that the lowest prices of hydrogen and electricity generated, with $ 2.092/kg and $ 11.495/kWh, were related to Grid and PV-Wind-Grid scenarios, respectively. Also, results indicated that Ar-Ruways station and PV-Wind-Grid scenario were the most environmentally suitable options that resulted in a CO2 emission rate of 1434 kg annually. To select just one station among five areas, a fuzzy method was deployed as a prioritization technique. Its results suggested that Doha Intl Airport site is the most suitable one for constructing solar-wind hybrid energy generation system. 相似文献
7.
《International Journal of Hydrogen Energy》2020,45(11):6838-6847
N-ethylcarbazole/dodecahydro-N-ethylcarbazole (NECZ/12H-NECZ) was a promising system for hydrogen storage applications. 1.0 wt% Pt/TiO2 was regarded as the optimal loading in Pt/TiO2 catalyst applied in the 12H-NECZ dehydrogenation reaction. The hydrogen release amount, selectivity to NECZ and TOF of 12H-NECZ dehydrogenation are 5.75 wt %, 98% and 229.73 min−1 at 453 K. Compared with the commercial 5.0 wt% Pd and Pt-based catalysts, it exhibited very high activity, selectivity and stability for 12H-NECZ dehydrogenation with low Pt loading. Combined with the XRD, XPS, HRTEM, TPR analysis, it was indicated that the enhanced catalytic performance was due to the SMSI (strong metal-supporting interaction) between Pt and TiO2 support, which accelerated the rate-limiting step and enhanced the whole dehydrogenation reaction. This work may be beneficial for the commercial application of Pt/TiO2 catalysts in the Liquid Organic Hydrogen Carrier (LOHC) system. 相似文献
8.
A novel batch plant for supercritical CO2 applications is proposed which is not equipped with expensive components, such as high‐pressure pumps, making it particularly suitable for bench‐scale use. For the first time, the use of a hanging scale is suggested to weigh the amount of CO2 required for the experiment and the use of the thermodynamics to reach the working conditions. The rig is able to cover different applications, e.g., aerogel drying, impregnation, and extraction, showing high flexibility. An approximate cost analysis has been performed considering as a reference a 150‐mL vessel. It has been calculated that both the setup and running costs are considerably lower than the common batch and semicontinuous rigs. 相似文献
9.
《International Journal of Hydrogen Energy》2020,45(41):21722-21737
Battery Electric Vehicles (BEVs) and Fuel Cell Electric Vehicles (FCEVs) have gained attention due to the growing concern about air quality in large urban centers. Barriers such as high purchase price and the lack of a supply infrastructure delay the mass adoption of these vehicles. The current work uses the Advanced Vehicle Simulator (ADVISOR) to analyze the influence of the degree of hybridization (DOH) on the performance and total cost of an FCEV (Hyundai Nexo 2019 model). The costs and fuel economy results of the different configurations (different DOH) are compared to those of the original vehicle. The configuration with the highest degree of hybridization (DOH = 61.2%) showed an 8.3% increase in fuel economy and a total cost reduction of 13.2% compared to the original vehicle. In addition, the best vehicle configuration results are compared to a same-segment gasoline-internal combustion engine vehicle and the original Hyundai Nexo in different cost scenarios. 相似文献
10.