ONLINE OPTIMAL CONTROL STRATEGY METHODOLOGY FOR POWER-SPLIT HYBRID ELECTRIC BUS BASED ON HISTORICAL DATA

Xiaohua Zeng,Zhenwei Wang,Yue Wang,Dafeng Song 한국자동차공학회 2020 International journal of automotive technology Vol.21 No.5

An online optimal control strategy methodology on the basis of historical data for a power-split hybrid electric bus (HEB) is proposed in this study. This approach aims to fully utilize the fuel-saving capability of power-split HEB under real operating cycles and provide an effective way for solving the optimal calibration problem in the application promotion. Firstly, a procedure for synthesizing real-world driving cycles based on cluster analysis and Markov chain method is constructed. Subsequently, dynamic programming (DP) control algorithm is performed to explore the fuel economy potential. Moreover, a DP-based rule control strategy with an automated implementation foundation is introduced to achieve online approximate optimal effect. Finally, offline simulation and hardware-in-the-loop test are conducted. Simulation results validate that the proposed online optimal control strategy methodology has similar fuel-saving performance to DP optimal results and good real-time application conditions

Anti-inflammatory and Anti-nociceptive Activities of Compounds from Tinospora sagittata (Oliv.) Gagnep.

Xiaohua Liu,Zhenlin Hu,Qirong Shi,Huawu Zeng,Yunheng Shen,Huizi Jin,Wei-Dong Zhang 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.7

Radix Tinosporae is a herb widely used in traditional Chinese medicine for the treatment of various inflammatory diseases. In the present study, its anti-inflammatory and antinociceptive activities were investigated. The ethanol extract of Radix Tinosporae exhibited significant inhibitory effects on xylene-induced ear edema and acetic acid-induced writhing in mice. Using bioassay-guided fractionation, the n-butanol fraction was determined as the active fraction. Further purification of the most active n-butanol fraction led to the isolation of three compounds, palmatine, columbamine and columbinyl glucoside. All three compounds showed inhibitory activities on xylene-induced ear edema, but only palmatine and columbamine exhibited significant inhibitory effects on acetic acid-induced writhing. In addition, palmatine and columbamine markedly inhibited in vitro production of nitric oxide and nuclear factor-κB activation in RAW264.7 macrophage cells in response to lipopolysaccharide or tumor necrosis factor α stimulation. These results provide justification for the utilization of Radix Tinosporae in Chinese folk medicine for the treatment of inflammatory diseases.

The Potentials in Solar Cells for MEH-PPV Derivatives: Molecular Design and Performance Prediction

Xiaohua Xie,Xu Liu,Dan Zeng,Longfeng Zhao 대한화학회 2020 Bulletin of the Korean Chemical Society Vol.41 No.7

In this contribution, the polymer poly(2-methoxy-5(2?-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) is researched at the aspect of electronic and structural properties to locate the relationships between structures and the experimental properties by employing DFT and TD-DFT method. The studied properties refer to the geometry features, absorption spectra, frontier molecular orbital properties, hole transport properties, and exciton dissociation ability at polymer/PC61BM interface. In addition, four MEH-PPV derivatives, MEH-PPV substituted with F atoms, are designed and studied through comparing with the properties of MEH-PPV. The results indicate that MEH-PPV has low HOMO levels and large hole transport property, which result in its preferable performance. Besides, the designed polymers are promising candidates as PSC donors due to better exciton dissociation ability and larger theoretical VOC owing to lower highest occupied molecule levels, in special, MEH-PPV-Fc has better hole transport properties than MEH-PPV due to smaller m*.

ARCHITECTURE OF FLOWER-LIKE rGO/CNTs-LOADED CuxO NANOPARTICLES AND ITS PHOTOCATALYTIC PROPERTIES

BIN ZENG,XIAOHUA CHEN,XUTAO NING,CHUANSHENG CHEN,HUI LONG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.5

Novel flower-like composite architecture was successfully synthesized by spray drying and post-calcinating method for the first time. Scanning electron microscopy and transmission electron microscopy observations confirmed that reduced graphene oxides/carbon nanotubes hybrid (rGO/CNTs) formed a flower-like micrometer structure and Cu2O, CuO (CuxO, x = 1 or 2) nanoparticles were decorated inside them. The photocatalytic properties were further investigated by evaluating the photodegradation of a pollutant methyl orange (MO). The experimental results indicated that this novel architecture enhanced photocatalytic performance with 96.2% decomposition of MO after 25 min in the presence of H2O2 under visible light irradiation, which was much higher than that of CuxO powders (33.2%). This could be attributed to the more efficient adsorption of MO molecules on flower-like rGO/CNTs and provide a high concentration of MO near to the CuxO nanoparticles, thus promoting the photocatalytic degradation process.

Research on dynamic decoupling control of air supplying loop in fuel cell system based on pressure compensation

Dafeng Song,Fanyong Zeng,Xiaohua Zeng,Qingtao Wu 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.6

This study establishes a simulation model of the voltage output of a fuel cell stack based on its basic design parameters. Under the condition that the number of cells in the stack remains unchanged, the output capacity of the stack from the control level is explored to increase the power level. This study optimizes the system, analyzes the game process between the parasitic power supply system and the output power of the fuel cell stack, and optimizes the output capacity of the fuel cell stack by compensating the backpressure. To strengthen the flow-pressure coupling during pressure compensation, the principle of autodisturbance decoupling control is applied to the strong coupling system to design a flowpressure dynamic decoupling controller that can weaken the flow-pressure coupling effect.

Energy Management Strategy of Plug-In Hybrid Electric Vehicles Considering Thermal Characteristics

Song Dafeng,Bi Daokun,Zeng Xiaohua,Wang Shiyuan 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.3

In order to explore the influence of the thermal management system (TMS) on vehicle energy management and tap the energy saving potential of TMS, this study establishes a vehicle energy management strategy control model oriented to reduce energy consumption of the TMS based on MATLAB/Simulink for a plug-in hybrid electric vehicle with planetary hybrid configuration. Firstly, a simulation model of vehicle dynamic machine - electric - thermal coupling working process is introduced, to evaluate the impact of TMS in the high and low temperature environment on energy consumption of the vehicle running. Then, based on the equivalent fuel consumption minimum strategy (ECMS) and considering the influence of TMS on energy consumption, an adaptive equivalent consumption minimum strategy model considering thermal characteristics (TAECMS) is established, which propose an improved adaptive equivalent factor adjustment method considering the thermal characteristics of the system is proposed. By establishing the Hamiltonian function to achieve the goal of minimum equivalent fuel consumption, considering the temperature penalty, the power of the engine and the power of the battery is reasonably allocated. Finally, the TAECMS control strategy achieves fuel saving of 6.2 % and 8.4 % respectively in high and low temperature environments through simulation verification and comparison.

Does Risk-taking Promote New Product Development Performance? An Environmental Dynamism Perspective

Yunfeng Peng,Jiao Xue,Saixing Zeng,Xiaohua Meng 한국증권학회 2018 Asia-Pacific Journal of Financial Studies Vol.47 No.3

Using an “entrepreneurial orientation–performance” framework and environmental contingency theory, this study proposes and empirically explores a theoretical framework for understanding the impacts of risk-taking and environmental dynamism on new product development (NPD) performance in emerging markets. We deepen the analysis of environmental dynamism into customer, competitor, supplier, institutional environment, and economic environment. The results demonstrate that risk-taking and environmental dynamism contribute both individually and interactively to the performance of NPD. Further, of all the environmental units, environmental dynamism from suppliers and regulatory groups has a significant, direct and positive moderating effect on the performance of NPD.

Inferring Sequential Order of Somatic Mutations during Tumorgenesis based on Markov Chain Model

Hao Kang,Kwang-Hyun Cho,Zhang, Xiaohua Douglas,Tao Zeng,Luonan Chen IEEE 2015 IEEE/ACM transactions on computational biology and Vol.12 No.5

<P>Tumors are developed and worsen with the accumulated mutations on DNA sequences during tumorigenesis. Identifying the temporal order of gene mutations in cancer initiation and development is a challenging topic. It not only provides a new insight into the study of tumorigenesis at the level of genome sequences but also is an effective tool for early diagnosis of tumors and preventive medicine. In this paper, we develop a novel method to accurately estimate the sequential order of gene mutations during tumorigenesis from genome sequencing data based on Markov chain model as TOMC (Temporal Order based on Markov Chain), and also provide a new criterion to further infer the order of samples or patients, which can characterize the severity or stage of the disease. We applied our method to the analysis of tumors based on several high-throughput datasets. Specifically, first, we revealed that tumor suppressor genes (TSG) tend to be mutated ahead of oncogenes, which are considered as important events for key functional loss and gain during tumorigenesis. Second, the comparisons of various methods demonstrated that our approach has clear advantages over the existing methods due to the consideration on the effect of mutation dependence among genes, such as co-mutation. Third and most important, our method is able to deduce the ordinal sequence of patients or samples to quantitatively characterize their severity of tumors. Therefore, our work provides a new way to quantitatively understand the development and progression of tumorigenesis based on high throughput sequencing data.</P>

Multi-objective optimization of drive gears for power split device using surrogate models

Jixin Wang,Wanghao Shen,Zhongda Wang,Mingyao Yao,Xiaohua Zeng 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.6

Power split device (PSD) is a key component in the energy coupling and decoupling of parallel-series hybrid electric vehicle. This paperproposes a multi-objective optimization method to achieve optimal balance solution among the volume, contact stress, and frictionalenergy dissipation of PSD drive gears, some of which are implicit with respect to design variables. To avoid the time-consuming problemof finite element analysis used to solve nonlinear responses, surrogate models are adopted to generate approximate expressions of designvariables. Pareto-optimal solutions of PSD are obtained using multi-island genetic algorithm (GA), non-dominated sorting GA-II(NSGA-II), and multi-objective particle swarm optimization algorithm. The performances of PSD before and after optimization are compared. Results indicate that the proposed method is effective, and NSGA-II achieves higher optimizing efficiency in solving the multiobjectiveoptimization problem of PSD than the other algorithms.