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《Oil and Energy Trends》2020,45(10):48-49
Net earnings after pre-tax profits. Profiles include: Anadarko Petroleum, Chevron Texaco, Conoco Phillips, Exxon Mobil, Occidental, Schlumberger, YPF SA, EnCana Corporation, Imperial Oil, Petroleo Brasileiro, Total SA, E.ON, ENI, Repsol, Ecopetrol SA, Norsk Hydro, Statoil, Devon Energy Corporation. BP, Shell, BHP Billiton, CNOOC, Sinopec and PetroChina. Updated on a monthly basis. 相似文献
3.
《Oil and Energy Trends》2020,45(12):46-47
Net earnings after pre-tax profits. Profiles include: Anadarko Petroleum, Chevron Texaco, Conoco Phillips, Exxon Mobil, Occidental, Schlumberger, YPF SA, EnCana Corporation, Imperial Oil, Petroleo Brasileiro, Total SA, E.ON, ENI, Repsol, Ecopetrol SA, Norsk Hydro, Statoil, Devon Energy Corporation. BP, Shell, BHP Billiton, CNOOC, Sinopec and PetroChina. Updated on a monthly basis. 相似文献
4.
The supervision of a hybrid power plant, including solar panels, a gas microturbine and a storage unit operating under varying solar power profiles is considered. The Economic Supervisory Predictive controller assigns the power references to the controlled subsystems of the hybrid cell using a financial criterion. A prediction of the renewable sources power is embedded into the supervisor. Results deteriorate when the solar power is unsteady, owing to the inaccuracy of the predictions for a long-range horizon of 10 s. The receding horizon is switched between an upper and a lower value according to the amplitude of the solar power trend. Theoretical results show the relevance of horizon switching, according to a tradeoff between performance and prediction accuracy. Experimental results, obtained in a Hardware In the Loop (HIL) framework, show the relevance of the variable horizon approach. Power amplifiers allow us to simulate virtual components, such as a gas microturbine, and to blend their powers with that of real devices (storage unit, real solar panels). In this case, fuel savings, reaching 15%, obtained under unsteady operating conditions lead to a better overall performance of the hybrid cell. The overall savings obtained in the experiments amount to 12%. 相似文献
5.
《International Journal of Hydrogen Energy》2022,47(26):13157-13167
The impact of dual fuel (diesel/hydrogen) on different performance aspects of CRDI diesel engines is investigated in this study. Amongst the fuel alternatives for IC (internal combustion) engines, the research described in this study recommended hydrogen as the least polluting and renewable in the long term. A CNG-LPG injector feeds hydrogen into the intake manifold, while diesel injectors pump pilot diesel to a DI engine adapted to hydrogen and diesel (dual-fuel mode). By maintaining 5.2 KW of consistent IP (Indicated Power) and engine speed at 1500 ± 10 rotations per minute (RPM), the hydrogen energy was varied in the dual fuel at 0% (100% diesel), 6%, 12%, 18% and 24%. With the increase in H2 energy proportion, a decrease (5.2% decrease at 24% HES) in the BSEC (brake specific energy consumption) and the engine's BTE (brake thermal efficiency) is improved (7.85% increase at 24% HES). When emissions are considered, indicated NOx increased (3.42%) while indicated CO2 (3.61%), CO (2.84%), and smoke (4.85%) decreased with an increase in the proportion of hydrogen. Along with this, it was noted that the peak HRR (heat release rate) of 69.8 J/deg and in-cylinder pressure of 80.8 bar which increased significantly with the increase in hydrogen rate. 相似文献
6.
《Oil and Energy Trends》2020,45(11):54-55
Net earnings after pre-tax profits. Profiles include: Anadarko Petroleum, Chevron Texaco, Conoco Phillips, Exxon Mobil, Occidental, Schlumberger, YPF SA, EnCana Corporation, Imperial Oil, Petroleo Brasileiro, Total SA, E.ON, ENI, Repsol, Ecopetrol SA, Norsk Hydro, Statoil, Devon Energy Corporation. BP, Shell, BHP Billiton, CNOOC, Sinopec and PetroChina. Updated on a monthly basis. 相似文献
7.
Haze is a poor-quality state described by the opalescent appearance of the atmosphere which reduces the visibility. It is caused by high concentrations of atmospheric air pollutants, such as dust, smoke and other particles that scatter and absorb sunlight. The poor visibility can result in the failure of multiple computer vision applications such as smart transport systems, image processing, object detection, surveillance etc. One of the major issues in the field of image processing is the restoration of images that are corrupted due to different degradations. Typically, the images or videos captured in the outside environment have low contrast, colour fade and restricted visibility due to suspended particles of the atmosphere that directly influence the image quality. This can cause difficulty in identifying the objects in the captured hazy images or frames. To address this problem, several image dehazing techniques have been developed in the literature, each of which has its own advantages and limitations, but effective image restoration remains a challenging task. In recent times, various learning (Machine learning & Deep learning) based methods greatly condensed the drawbacks of manual design of haze related features and reduces the difficulty in efficient restoration of images with less computational time and cost. The current state-of-the-art methods for haze free images, mainly from the last decade, are thoroughly examined in this survey. Moreover, this paper systematically summarizes the hardware implementations of various haze removal methods in real time. It is with the hope that this current survey acts as a reference for researchers in this scientific area and to provide a direction for future improvements based on current achievements. 相似文献
8.
本文结合HTH电路的复杂性等特征分析与实际应用现状,研究了HTH电路的具体检测技术方法并对当前热点技术进行对比分析,探讨了HTH电路检测方法的技术发展趋势。 相似文献
9.
The liberalization of television markets and the emergence of commercial channels has changed the position of public television, bringing an end to monopolies. Public television now competes for audiences with private television. In this paper, the authors analyze the changes to the market position of public television in Germany, Spain, France, the United Kingdom (UK), and Italy between 1995 and 2019. In this 25-year period, all of these countries have had a liberalized TV market. The aim of this paper is to demonstrate the ways in which public television competes with commercial television, assessing the consequences of this on market power. This analysis allows us to detect similarities and dissimilarities between public television and television markets in large Western European countries. The results show the decline of the market share of public television in all countries, except Germany. Furthermore, public television has remained market leading in all countries, with the exception of Spain. One of the ways to compete with commercial television is to start new public channels and acquire a large audience. 相似文献
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