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Metagenomic insights into the profile of antibiotic resistomes in sediments of aquaculture wastewater treatment system

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Journal of Environmental Sciences 2022年第3期34卷 345-355页

作者： Jianfei Chen Yuyin Yang Xinshu Jiang Yanchu Ke Tao He Shuguang Xie State Key Joint Laboratory of Environmental simulation and Pollution control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Joint Laboratory of Environment simulation and Pollution control(SKJLESPC) Beijing Key Laboratory for Emerging Organic Contaminants Control(BKLEOC)School of EnvironmentPOPs Research CenterTsinghua UniversityBeijing 100084China South China Institute of Environmental Sciences(SCIES) Ministry of Ecology and Environment(MEE)Guangzhou 510655China

To meet the rapidly growing global demand for aquaculture products,large amounts of antibiotics were used in aquaculture,which might accelerate the evolution of antibiotic-resistant bacteria(ARB)and the propagation of antibiotic genes(ARGs).In our research,we revealed the ARGs profiles,their co-occurrence with mobile genetic elements(MGEs),and potential hosts in sediments of a crab pond wastewater purification system based on metagenomic analysis.The residual antibiotic seems to increase the propagation of ARGs in the crab pond,but there was no clear relationship between a given antibiotic type and the corresponding resistance genes.The effect of aquaculture on sediment was not as profound as that of other anthropogentic activities,but increased the relative abundance of sulfon-amide resistance gene.A higher abundance of MGEs,especially plasmid,increased the po-tential ARGs dissemination risk in crab and purification ponds.Multidrug and sulfonamide resistance genes had greater potential to transfer because they were more frequently carried by MGEs.The horizontal gene transfer was likely to occur among a variety of microorgan-isms,and various ARGs hosts including Pseudomonas,Acinetobacter,Escherichia,and Klebsiella were identified.Bacterial community influenced the composition of ARG hosts,and Pro-teobacteria was the predominant hosts.Overall,our study provides novel insights into the environmental risk of ARGs in sediments of aquaculture wastewater treatment system.

关键词： Metagenomic sequencing Aquaculture Antibiotic resistome Antibiotic resistance genes(ARGs) Mobile genetic elements(MGEs) ARG hosts

Improved adaptive pruning algorithm for least squares support vector regression

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Journal of Systems Engineering and Electronics 2012年第3期23卷 438-444页

作者： Runpeng Gao Ye San Control and Simulation Center Harbin Institute of TechnologyHarbin 150001P.R.China

As the solutions of the least squares support vector regression machine （LS-SVRM） are not sparse, it leads to slow prediction speed and limits its applications. The defects of the ex- isting adaptive pruning algorithm for LS-SVRM are that the training speed is slow, and the generalization performance is not satis- factory, especially for large scale problems. Hence an improved algorithm is proposed. In order to accelerate the training speed, the pruned data point and fast leave-one-out error are employed to validate the temporary model obtained after decremental learning. The novel objective function in the termination condition which in- volves the whole constraints generated by all training data points and three pruning strategies are employed to improve the generali- zation performance. The effectiveness of the proposed algorithm is tested on six benchmark datasets. The sparse LS-SVRM model has a faster training speed and better generalization performance.

关键词： least squares support vector regression machine （LS- SVRM） pruning leave-one-out （LOO） error incremental learning decremental learning.

Analysis on carbon emission reduction intensity of fuel cell vehicles from a life-cycle perspective

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Frontiers in Energy 2024年第1期18卷 16-27页

作者： Ziyuan TENG Chao TAN Peiyuan LIU Minfang HAN Fuel Cell and Energy Storage center Department of Energy and Power EngineeringState Key Laboratory of Control and Simulation of Power Systems and Generation EquipmentTsinghua UniversityBeijing 100084China

The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and neutrality.This paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys,including hydrogen production and packing in chlor-alkali plants,transport by tube trailers,storage and refueling in hydrogen refueling stations(HRSs),and application for use in two different cities.It also conducted a comparative study for battery electric vehicles(BEVs)and internal combustion engine vehicles(ICEVs).The result indicates that hydrogen fuel cell vehicle(FCV)has the best environmental performance but the highest energy cost.However,a sufficient hydrogen supply can significantly reduce the carbon intensity and FCV energy cost of the current system.The carbon emission for FCV application has the potential to decrease by 73.1%in City A and 43.8%in City B.It only takes 11.0%–20.1%of the BEV emission and 8.2%–9.8%of the ICEV emission.The cost of FCV driving can be reduced by 39.1%in City A.Further improvement can be obtained with an economical and“greener”hydrogen production pathway.

关键词： hydrogen energy life-cycle assessment(LCA) fuel cell vehicle carbon emission energy cost

Solving Multi-Stage Weapon Target Assignment Problems by C-TAEA

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Solving Multi-Stage Weapon Target Assignment Problems by C-T...

第三十九届中国控制会议

作者： Shiqi Zou Xiaoping Shi Rui Guo Xiaohan Lin Control and Simulation Center Harbin Institute of Technology

Multi-stage weapon target assignment(MSWTA) problem is usually treated as a classical constrained multi-objective optimization problem, which tends to balance the attack efficiency and economic loss for weapons after adding engagement resource constraints. In the context of multi-stage confrontations, the MSWTA becomes more complex and challenging to solve. To handle this constrained problem, this paper develops the advantageous two-archive evolutionary algorithm(C-TAEA) to combine the density estimation mechanism with a fast non-dominated sorting method to obtain solutions to this problem efficiently, while maintaining the convergence-oriented archive(CA) to speed up the generation of solutions and the diversity-oriented archive(DA) to enhance the diversity of populations. Extensive experiments are conducted to compare the proposed C-TAEA with the traditional NSGA-Ⅱ according to the average of IGD and HV values. The numerical simulation results demonstrate that our method intuitively shows the performance improvement after adding the feasibility and can find the approximate Pareto Front more effectively.

关键词： Weapon Target Assignment（WTA） Multi-Objective Optimization Problem Two-Archive C-TAEA NSGA-Ⅱ Density Estimation

On Stability Analysis of Varying-speed Tilting Flywheel under Two Distinct control Schemes

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On Stability Analysis of Varying-speed Tilting Flywheel unde...

第三十九届中国控制会议

作者： Zhe Wang Yuanyuan Zhang Xin Huo Qing Zhao Hui Zhao Songlin Chen Control and Simulation Center Harbin Institute of Technology

Varying-speed Tilting Flywheel（VSTF） is an innovative device that combines the actuating capabilities of the control moment gyro with the rate sensing capabilities of the tuned rotor gyro by using a spinning flex-gimbal system. Precession and nutation stability of high-speed rotor is the primary factor determining stability of the VSTF system. In this paper, a simplified mathematical model of VSTF is established, based on which the complex coefficient transfer function is derived and the classical Nyquist criterion using Bode diagram can be extended to the complex coefficient frequency domain. Then, the double-frequency Bode diagram and the Nyquist criterion are used for analyzing the stability of the VSTF system and designing the parameters of the PD controller and adaptive nutation damper. simulation results are presented to verify the effectiveness of two distinct control schemes and the proposed stability analysis method.

关键词： VSTF Stability Analysis Complex Coefficient Transfer Function Double-frequency Bode Diagram

Design of Reusable Effectiveness Evaluation Model Framework

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Design of Reusable Effectiveness Evaluation Model Framework

第32届中国控制与决策会议

作者： Shuang Zhang Wei Li Shenglin Lin Ming Yang Jiahui Tong Control and Simulation Center Harbin Institute of Technology

In order to make the effectiveness evaluation models of the weapon equipment system universal and flexible,and adapt to different evaluation objects,a framework of effectiveness evaluation model is designed.Next a series of modular and reusable effectiveness evaluation models are proposed under the framework.Each type of evaluation model is built based on IDEF0,and the corresponding input and output of each model are designed.To further improve reusability,several models are mathematically described and model interface is designed based on XML.

关键词： Effectiveness Evaluation Evaluation Model Modular Reuse

control Design for Current Loop of PMSM Using A Modified Model-Compensation ADRC controller

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Control Design for Current Loop of PMSM Using A Modified Mod...

第三十九届中国控制会议

作者： Yingning Gao Hui Zhao Kemao Ma Xin Huo Control and Simulation Center Harbin Institute of Technology

Active disturbance rejection control（ADRC） is now widely applied in motor drives due to its advantages like independence of system models and better disturbance rejection ability. For the current loop of PMSM, the uncertainties like model coupling and parameter variation can be estimated and compensated by ADRC. Considering that the total disturbance of current loop can be partially compensated for by available plant characteristics, the idea of model compensation can be applied to ADRC controller. However, the filter link in current feedback loop is usually ignored in conventional model compensation approach. Therefore, a modified model-compensation ADRC current control strategy considering the filter link effect is proposed in this paper, with simulation results show that better current tracking performance is achieved by the proposed control strategy.

关键词： Model-Compensation ADRC Total disturbance Filter link Current loop

Recent advances and perspectives towards emission inventories of mobile sources:Compilation approaches,data acquisition methods,and case studies

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Journal of Environmental Sciences 2023年第1期123卷 460-475页

作者： Han Jiang Hefeng Zhang Mingliang Fu Zhihui Huang Hong Ni Hang Yin Yan Ding State Environmental Protection Key Laboratory of Vehicle Emission control and simulation Chinese Research Academy of Environmental SciencesBeijing 100012China Vehicle Emission control center of Ministry of Ecology and Environment Chinese Research Academy of Environmental SciencesBeijing 100012China

In recent years,great efforts have been devoted to reducing emissions from mobile sources with the dramatic growth of motor vehicle and nonroad mobile source populations.Compilation of a mobile source emission inventory is conducive to the analysis of pollution emission characteristics and the formulation of emission reduction policies.This study summarizes the latest compilation approaches and data acquisition methods for mobile source emission inventories.For motor vehicles,a high-resolution emission inventory can be developed based on a bottom-up approach with a refined traffic flow model and real-world speed-coupled emission factors.The top-down approach has advantages when dealing with macroscale vehicle emission estimation without substantial traffic flow infrastructure.For nonroad mobile sources,nonroad machinery,inland river ships,locomotives,and civil aviation aircraft,a top-down approach based on fuel consumption or power is adopted.For ocean-going ships,a bottom-up approach based on automatic identification system(AIS)data is adopted.Three typical cases are studied,including emission reduction potential,a cost-benefit model,and marine shipping emission control.Outlooks and suggestions are given on future research directions for emission inventories for mobile sources:building localized emission models and factor databases,improving the dynamic updating capability of emission inventories,establishing a database of emission factors of unconventional pollutants and greenhouse gas from mobile sources,and establishing an urban high temporalspatial resolution volatile organic compound(VOC)evaporation emission inventory.

关键词： Emission inventory Mobile source Emission factor Emission control policy

Non-layer-transformed Mn_(3)O_(4) cathode unlocks optimal aqueous magnesium-ion storage via synergizing amorphous ion channels and grain refinement

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Journal of Energy Chemistry 2022年第5期31卷 42-48页

作者： Zhongyu Pan Tingting Qin Wei Zhang Xianyu Chu Taowen Dong Nailin Yue Zizhun Wang Weitao Zheng State Key Laboratory of Automotive simulation and control School of Materials Science&EngineeringKey Laboratory of Mobile Materials MOEElectron Microscopy Centerand International Center of Future ScienceJilin UniversityChangchun 130012JilinChina

Aqueous rechargeable magnesium ion batteries(ARMBs) have obtained more attention due to the twoelectrons transfer nature, low cost and safety. However, the scarcity of cathode materials seriously hinders the development of ARMBs because of the unfavorable strong interaction between Mg^(2+) and cathode material. Herein, we choose a pre-treated spinel Mn_(3)O_(4) cathode for aqueous Mg^(2+) storage. The pretreatment in Na_(2)SO_(4) solution induces the grain refinement decorated with tortuous amorphous ion diffusion channels, facilitating the production of electrochemical reaction active sites and the diffusion of Mg^(2+), respectively, which achieve a(sub-)surface pseudocapacitance reaction between Mn(Ⅱ) and Mn(Ⅲ). As a result, the pre-treated Mn_(3)O_(4) cathode exhibits a package of optimal performances, i.e., a capacity of 98.9 m Ah g^(-1) and a high capacity retention rate of 99.4% after 2000 cycles. To the best of our knowledge, our work not only provides a new reaction mechanism of spinelMn_(3)O_(4) in aqueous batteries system,but also affords a high cycle stability electrode material for rechargeable Mg^(2+) energy storage.

关键词： Spinel Mn3O4 Grain refinement Amorphous ARMBs