Reinforcement Learning Based Gasoline Blending Optimization: Achieving More Efficient Nonlinear Online Blending of Fuels

The online optimization of gasoline blending benefits refinery economies. However, the nonlinear blending mechanism, the oil property fluctuations, and the blending model mismatch bring difficulties to the optimization. To solve the above issues, this paper proposes a novel online optimization method based on deep reinforcement learning algorithm (DRL). The Markov decision process (MDP) expression are given considering a practical gasoline blending system. Then, the environment simulator of gasoline blending process is established based on the MDP expression and the one-year measurement data of a real-world refinery. The soft actor-critic (SAC) DRL algorithm is applied to improve the DRL agent policy by using the data obtained from the interaction between DRL agent and environment simulator. Compared with a traditional method, the proposed method has better economic performance. Meanwhile, it is more robust under property fluctuations and component oil switching. Furthermore, the proposed method maintains performance by automatically adapting to system drift.Comment: 30 pages,13 figure

Hilbert-Huang Transform based multifractal analysis of China stock market

National Natural Science Foundation of China (NSFC) [11202122, 11301433, 11332006]; 'Pu Jiang' project of Shanghai [12PJ1403500]; Social Science Foundation of Fujian [2013C056]In this paper, we employ the Hilbert-Huang Transform to investigate the multifractal character of Chinese stock market based on CSI 300 index. The measured Hilbert moment L-q(omega) shows a power-law behavior on the range 0.01 < omega < 0.1 min(-1), equivalent to a time scale range 10 < tau < 100 min. The measured scaling exponents zeta (q) is convex with q and deviates from the value q/2, implying that the property of self-similarity is broken. Moreover, zeta (q) and the corresponding singularity spectrum D(h) can be described by a lognormal model with a Hurst number H = 0.50 and an intermittency parameter mu = 0.12. Our results suggest that the Chinese stock fluctuation might be captured well by a multifractal random walk model with a proper intermittency parameter. (C) 2014 Elsevier B.V. All rights reserved

Analysis of Ecological Efficiency, Ecological Innovation, Residents’ Well-Being and Their Improvement Paths in Chinese Resource-Based Cities—Based on the Approaches of Two-Stage Super-SBM and fsQCA

Over the past decades, resource-based cities have played a significant role in the development of countries worldwide. China, as a representative developing country, has seen the vital role played by resource-based cities in its development progress. However, heavy reliance on resources in these cities leads to environmental issues. The challenge lies in achieving ecological innovation and enhancing residents’ well-being within resource and environmental constraints for sustainable regional development. This study introduces a two-stage super slacks-based measure (super-SBM) approach to assess the ecological efficiency (EE), ecological innovation (EI), and residents’ well-being (RW) efficiency of 92 sample resource-based cities in China, and presents spatial and grouping comparisons. Then, the fuzzy-set qualitative comparative analysis method (fsQCA) is applied to identify paths and development orientations for sustainable development. The results show that resource-based cities in southwest and northwest China exhibit strong performance in EE, EI, and RW, while those in the northeast perform poorly. Growth and maturity resource-based cities demonstrate favorable development in EE and EI, whereas recession and regeneration resource-based cities show unsatisfactory development. The RW efficiency tends to stabilize after the rapid growth of the 92 sample resource-based cities. The fsQCA reveals five paths to achieving high EE, three paths for high EI efficiency, and two paths for high RW efficiency. These paths can be categorized into four development orientations: scale-oriented, economic-oriented, integrated-oriented, and transformation-oriented. These results provide essential references for the development planning and strategic formulation not only in China but also in other similar resource-based cities globally

Analysis of land use dynamic econometric change in Chaohu basin from 2000 to 2015

Chaohu basin is located in the central economic belt, as an important part of the Yangtze River Basin. Based on the data of land use classification from 2000 to 2015, this paper makes a dynamic econometric analysis on the spatial structure of land use in Chaohu basin. The results show that: (1) The agricultural land has been in a downward trend from 2000 to 2015. However, the construction land has been increasing. From 2005 to 2010, the change of agriculture and the construction land have reached the maximum value, which are -0.279% and 1.814%, respectively. (2) During 2000-2015, every five years, the change of land use degree in Chaohu basin is greater than 0. The land use in the study area is in the development period, among which the change of land use from 2000 to 2005 is the largest. (3) The information entropy of land use in Chaohu basin is more than 1, and the change of information entropy is more than 0, which indicates that the information entropy is on the rise and the land use is in disorder. The results are of practical significance to the ecological security and optimal regulation of Chaohu Basin

Mapping Urban Heat Vulnerability of Extreme Heat in Hangzhou via Comparing Two Approaches

Extreme heat is the leading cause of heat-related mortality around the world. Extracting heat vulnerability information from the urban complexity system is crucial for urban health studies. Using heat vulnerability index (HVI) is the most common approach for urban planners to locate the places with high vulnerability for intervention and protection. Previous studies have demonstrated that HVI can play a vital role in determining which areas are at risk of heat-related deaths. Both equal weight approach (EWA) and principal component analysis (PCA) are the conventional methods to aggregate indicators to HVI. However, seldom studies have compared the differences between these two approaches in estimating HVI. In this paper, we evaluated the HVIs in Hangzhou in 2013, employing EWA and PCA, and assessed the accuracies of these two HVIs by using heat-related deaths. Our results show that both HVI maps showed that areas with high vulnerability are located in the central area while those with low vulnerability are located in the suburban area. The comparison between HVIEWA and HVIPCA shows significantly different spatial distributions, which is caused by the various weight factors in EWA and PCA. The relationship between HVIEWA and heat-related deaths performs better than the relationship between HVIPCA and deaths, implying EWA could be a better method to evaluate heat vulnerability than PCA. The HVIEWA can provide a spatial distribution of heat vulnerability at intracity to direct heat adaptation and emergency capacity planning

Culturable bacterial endophytes of Aconitum carmichaelii Debx. were diverse in phylogeny, plant growth promotion, and antifungal potential

Medicinal plants harbor tremendously diverse bacterial endophytes that maintain plant growth and health. In the present study, a total of 124 culturable bacterial endophytes were isolated from healthy Aconitum carmichaelii Debx. plants. These strains were clustered into 10 genera based on full-length 16S rDNA sequences, among which Bacillus and Pseudomonas were the dominant genera. In addition, A. carmichaelii may capture 10 potential new bacterial species based on multi-locus sequence analysis of three housekeeping genes (gyrA, rpoB, and atpD). The majority of these bacterial endophytes exhibited plant growth-promoting ability through diverse actions including the production of either indole acetic acid and siderophore or hydrolytic enzymes (glucanase, cellulose, and protease) and solubilization of phosphate or potassium. A total of 20 strains inhibited hyphal growth of fungal pathogens Sclerotium rolfsii and Fusarium oxysporum in vitro on root slices of A. carmichaelii by the dual-culture method, among which Pseudomonas sp. SWUSTb-19 showed the best antagonistic activity. Field experiment confirmed that Pseudomonas sp. SWUSTb-19 significantly reduced the occurrence of southern blight and promoted plant biomass compared with non-inoculation treatment. The possible mode of actions for Pseudomonas sp. SWUSTb-19 to antagonize against S. rolfsii involved the production of glucanase, siderophore, lipopeptides, and antimicrobial volatile compounds. Altogether, this study revealed that A. carmichaelii harbored diverse plant growth-promoting bacterial endophytes, and Pseudomonas sp. SWUSTb-19 could be served as a potential biocontrol agent against southern blight

Research on Maximum Penetration Ratio of Wind Power under the Voltage Stability Margin Constraint

With the large-scale integration of wind power, the voltage stability problem in the power system has become increasingly prominent. Therefore, this paper studies the maximum penetration ratio of wind power from the perspective of voltage stability. Firstly, the mathematical grid-connection model of the wind generator is established. Secondly, using the impedance modulus margin index (IMMI) and the Thevenin model, the analytical calculation method for maximum wind power penetration under the voltage stability margin constraint is proposed with theoretical derivation. Then, a typical case study is used to verify the feasibility and effectiveness of the proposed method. Finally, based on this, the key factors affecting the wind power penetration limit are analyzed from the source&ndash;grid&ndash;load side, and practical engineering measures to improve the maximum penetration ratio of wind power are summarized. This research will be helpful for the planning and operation of the high-proportion renewable energy power systems