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Real-time pore structure evolution difference between deep and shallow coal during gas adsorption:A study based on synchrotron radiation small-angle X-ray scattering

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Particuology 2024年第4期87卷 114-123页

作者： Yingfeng Sun Shuaipeng zhu Fei Xie Chujian Han Yixin zhao Zetian Zhang Research Institute of Macro-Safety Science University of Science and Technology BeijingBeijing100083China Schoolof Civiland Resource Engineering University of Science and Technology BeijingBeijing100083China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230029China Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources China University of Mining and Technology(Beijing)Bejing10003 China School of Energy and Mining Engineering China University of Mining and Technology(Beijing)Beijing100083China Key Laboratory of Deep Earth Science and Engineering(Sichuan University) Ministry of EducationChengdu610065China

Coal seam CO_(2) sequestration is an important option to address global warming.A better knowledge on coal pore structure evolution during gas adsorption can provide guidance for coal seams CO_(2) ***,few investigations on the pore structure evolution differences between the deep and shallow coal were conducted during gas *** this study,based on the real-time synchrotron radiation small-angle X-ray scattering(SAXS)observation,the average pore diameter and pore surface fractal dimension evolution differences between deep and shallow coal were investigated from the as-pects of coal compositions and stress *** types of coal deformation(inner-swelling and outer-swelling)coexist during gas *** compositions have significant impact on the dominance of deformation *** dominance of inner-swelling in deep coal is induced by the higher ash contents,and there is the decrease of average pore diameter during gas *** impact of stress-history(burial depth)on adsorption-induced deformation is more prominent than that of gas adsorption *** deep coal,the surface fractal dimension evolution presents a negative correlation with the evolution of pore *** shallow coal,the surface fractal dimension evolution presents a Langmuir-type correlation with the adsorption time.

关键词： Coal Gas adsorption Synchrotron radiation small-angle X-ray scattering Pore diameter Surface fractal dimension

Gas exchange optimization in aircraft engines using sustainable aviation fuel:A design of experiment and genetic algorithm approach

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Energy and AI

Energy and AI 2024年第3期17卷 261-280页

作者： Zheng Xu Jinze Pei Shuiting Ding Longfei Chen Shuai zhao Xiaowei Shen Kun zhu Longtao Shao Zhiming zhong Huansong Yan Farong Du Xueyu Li Pengfei Yang Shenghui zhong Yu Zhou Hangzhou International Innovation Institute Beihang UniversityHangzhou311115China Research Institute of Aero-Engine Beihang UniversityBeijing102206China Civil Aviation University of China Tianjin300300China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beijing100083China Aero Engine Academy of China Beijing101304China School of Energy and Power Engineering Beihang UniversityBeijing100083China AVIC Chengdu Aircraft Design and Research Institute Chengdu610091China AVIC Nanjing Engineering Institute of Aircraft Systems Nanjing211106China School of Transportation Science and Engineering Beihang UniversityBeijing100083China Faculty of Science and Engineering University of Nottingham Ningbo ChinaNingbo315100China

The poppet valves two-stroke(PV2S)aircraft engine fueled with sustainable aviation fuel is a promising option for general aviation and unmanned aerial vehicle propulsion due to its high power-to-weight ratio,uniform torque output,and flexible valve ***,its high-altitude gas exchange performance remains unexplored,presenting new opportunities for optimization through artificial intelligence(AI)*** study uses validated 1D+3D models to evaluate the high-altitude gas exchange performance of PV2S aircraft *** valve timings of the PV2S engine exhibit considerable flexibility,thus the Latin hypercube design of experiments(DoE)methodology is employed to fit a response surface model.A genetic algorithm(GA)is applied to iteratively optimize valve timings for varying *** optimization process reveals that increasing the intake duration while decreasing the exhaust duration and valve overlap angles can significantly enhance high-altitude gas exchange *** optimal valve overlap angle emerged as 93°CA at sea level and 82°CA at 4000 m *** effects of operating parameters,including engine speed,load,and exhaust back pressure,on the gas exchange process at varying altitudes are further *** higher engine speed increases trapping efficiency but decreases the delivery ratio and charging efficiency at various *** effect is especially pronounced at elevated *** increase in exhaust back pressure will significantly reduce the delivery ratio and increase the trapping *** study demonstrates that integrating DoE with AI algorithms can enhance the high-altitude performance of aircraft engines,serving as a valuable reference for further optimization efforts.

关键词： Poppet valves two-stroke Design of experiment Genetic algorithm optimization Heavy fuel aircraft engine High altitude gas exchange performance

Unresolved Excess Accumulation of Myelin-Derived Cholesterol Contributes to Scar Formation after Spinal Cord Injury

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Research 2024年第1期2023卷 17-32页

作者： Bolin Zheng Yijing He Shuai Yin Xu zhu Qing zhao Huiyi Yang zhaojie wang Rongrong zhu Liming Cheng Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration Ministry of EducationDepartment of OrthopedicsTongji HospitalSchool of MedicineTongji UniversityShanghai 200092China Frontier Science Center for Stem Cell Research School of Life Science and TechnologyTongji UniversityShanghai 200092China Clinical Center for Brain and Spinal Cord Research Tongji UniversityShanghai 200092China

Spinal cord injury triggers complex pathological cascades,resulting in destructive tissue damage and incomplete tissue *** formation is generally considered a barrier for regeneration in the central nervous ***,the intrinsic mechanism of scar formation after spinal cord injury has not been fully ***,we report that excess cholesterol accumulates in phagocytes and is inefficiently removed from spinal cord lesions in young adult ***,we observed that excessive cholesterol also accumulates in injured peripheral nerves but is subsequently removed by reverse ***,preventing reverse cholesterol transport leads to macrophage accumulation and fibrosis in injured peripheral ***,the neonatal mouse spinal cord lesions are devoid of myelin-derived lipids and can heal without excess cholesterol *** found that transplantation of myelin into neonatal lesions disrupts healing with excessive cholesterol accumulation,persistent macrophage activation,and *** internalization suppresses macrophage apoptosis mediated by CD5L expression,indicating that myelin-derived cholesterol plays a critical role in impaired wound *** together,our data suggest that the central nervous system lacks an efficient approach for cholesterol clearance,resulting in excessive accumulation of myelin-derived cholesterol,thereby inducing scar formation after injury.

关键词： healing Spinal impaired

Research on Transmission Line Tower Tilting and Foundation State Monitoring Technology Based onMulti-Sensor Cooperative Detection and Correction

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Energy Engineering 2024年第1期121卷 169-185页

作者： Guangxin Zhang Minghui Liu Shichao Cheng Minzhen Wang Changshun zhao Hongdan zhao Gaiming zhong College of Science and Technology(CST) Ningbo UniversityNingbo315000China Dadong Power Supply Company State Grid Liaoning Electric Power Co.Ltd.Dandong118000China Dalian Power Supply Company State Grid Liaoning Electric Power Co.Ltd.Dalian116000China Yanbian Power Supply Company State Grid Jilin Electric Power Co.Ltd.Yanji133000China Liaoyuan Power Supply Company State Grid Jilin Electric Power Co.Ltd.Liaoyuan136200China

The transmission line tower will be affected by bad weather and artificial subsidence caused by the foundation and other factors in the power *** tower’s tilt and severe deformation will cause the building to *** small changes caused the tower’s collapse,but the early staff often could not intuitively notice the changes in the tower’s *** the current tower online monitoring system,terminal equipment often needs to replace batteries frequently due to premature exhaustion of *** to the need for real-time measurement of power line tower,this research designed a real-time monitoring device monitoring the transmission tower attitude tilting and foundation state based on the inertial sensor,the acceleration of 3 axis inertial sensor and angular velocity raw data to pole average filtering pre-processing,and then through the complementary filtering algorithm for comprehensive calculation of tilt angle,the system meets the demand for inclined online monitoring of power line poles and towers regarding measurement accuracy,with low cost and power *** optimization multi-sensor cooperative detection and correction measured tilt angle result relative accuracy can reach 1.03%,which has specific promotion and application value since the system has the advantages of unattended and efficient calculation.

关键词： Transmission line tower tilting multi-sensor foundation state monitoring collaborative detection

Transfer-based Approximate Dynamic Programmingfor Rolling Security-constrained Unit Commitment with Uncertainties

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Protection and Control of Modern Power Systems 2024年第5期9卷 42-53页

作者： Jianquan zhu Kai Zeng Jiajun Chen Wenmeng zhao Wenhao Liu Wenkai zhu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China Electric Power Research Institute China Southern Power GridGuangzhou 510700China

This paper studies the rolling security-constrained unit commitment(RSCUC)problem with AC power flow and *** this NP-hard problem,it is modeled as a Markov decision process,which is then solved by a transfer-based approximate dynamic programming(TADP)algorithm proposed in this *** from traditional approximate dynamic programming(ADP)algorithms,TADP can obtain the commitment states of most units in advance through a decision transfer technique,thus reducing the action space of TADP ***,compared with traditional ADP algorithms,which require to determine the commitment state of each unit,TADP only needs determine the unit with the smallest on-state probability among all on-state units,thus further reducing the action *** proposed algorithm can also prevent the iter-ative update of value functions and the reliance on rolling forecast information,which makes more sense in the rolling decision-making process of ***,nu-merical simulations are carried out on a modified IEEE 39-bus system and a real 2778-bus system to demonstrate the effectiveness of the proposed *** Terms-Rolling security-constrained unit com-mitment,approximate dynamic programming,decision transfer,probability-based decision priority criterion,uncertainty.

关键词： Rolling security-constrained unit com-mitment approximate dynamic programming decision transfer probability-based decision priority criterion uncertainty

Identification of reservoir types in deep carbonates based on mixedkernel machine learning using geophysical logging data

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Petroleum Science 2024年第3期21卷 1632-1648页

作者： Jin-Xiong Shi Xiang-Yuan zhao Lian-Bo Zeng Yun-zhao Zhang Zheng-Ping zhu Shao-Qun Dong Key Laboratory of Exploration Technologies for Oil and Gas Resources of the Ministry of Education Yangtze UniversityWuhan4310HubeiChina School of Geosciences Yangtze UniversityWuhan430100HubeiChina College of Geosciences China University of Petroleum(Beijing)Beijing102249China Petroleum Exploration and Production Research Institute of SINOPEC Beijing100083China School of Earth Sciences and Engineering Xi'an Shiyou UniversityXi'an 710065ShaanxiChina

Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage *** cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging ***,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ***,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data *** address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,*** MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input *** particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD *** evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM ***,the built MKFD model was applied in a blind well test,and a variable importance analysis was *** comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger *** MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.

关键词： Reservoir type identification Geophysical logging data Kernel Fisher discriminantanalysis Mixedkernel function Deep carbonates

维普期刊数据库

Influence of high-pressure heat treatment on magnetocaloric effects and magnetic phase transition in single crystal Gd3Ga5O12

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Journal of Rare Earths 2024年第11期42卷 2112-2118页

作者： Xiang Jin Jing zhao Lei Gao Huaijin Ma Haschuluu Oimod Hongwei zhu Qi Li Taichao Su Hongyu zhu Tegus O Jianjun zhao Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials Inner Mongolia Normal University School of Physical Science and Technology Baotou Teachers' CollegeKey Laboratory of Magnetism and Magnetic Materials for Higher Education in Inner Mongolia Autonomous Region National Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare Earths College of Science Guilin University of Technology

The magnetic properties and magnetic phase transition critical behavior of Gd3Ga5O12single crystals subjected to high-pressure heat treatment were *** results show that high-pressure heat treatment reduces the Curie temperature and magnetization of the *** a magnetic field change of 5 T,the maximum isothermal magnetic entropy of the sample is approximately 19.73 J/（kg·K）.High-pressure heat treatment increases the phase transition temperature range and leads to an increase in the magnetic refrigeration *** Gd3Ga5O12single crystals and the high-pressure heat-treated sample undergo a second-order phase *** critical behavior of the samples aligns with the mean field model acquired via critical model *** indicates that the samples exhibit long-range exchange interactions in the system near the Curie ***,this material can be used as a magnetic refrigerant for low-temperature applications.

关键词： High-pressure heat treatment Magnetic phase transition Magnetic refrigeration Magnetocaloric effect Rare earths

Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

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Defence Technology（防务技术） 2024年第8期38卷 155-170页

作者： Ning Liu Wenjiang zhao Yao Wang Kai Shen zhong Su Wenhao Qi Yuedong Xie Beijing Key Laboratory of High Dynamic Navigation Technology Beijing Information Science and Technology UniversityBeijing100192China Hua an Industry Group Co. Ltd.Qiqihar161006China Integrated Navigation and Intelligent Navigation Laboratory Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Beijing100081China

In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 *** this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized.

关键词： Guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)

维普期刊数据库

Regenerative Braking Energy Recovery System of Metro Train Based on Dual-Mode Power Management

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Energy Engineering 2024年第9期121卷 2585-2601页

作者： Feng zhao Xiaotong zhu Xiaoqiang Chen Ying Wang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strategy is ***,the construction of the hybrid regenerative braking energy recovery system is ***,based on the power demand of low-voltage load in metro stations,a dual-mode power management strategy is proposed to allocate the reference power of each system according to the different working conditions,and the control methods of each system are ***,the correctness and effectiveness of the dual-mode strategy are verified through simulation,and the proposed braking energy utilization scheme is compared with other singleform utilization *** results illustrate that the hybrid system with the dual-mode strategy can effectively recycle the regenerative braking energy of metro train and inhibit the busbar voltage fluctuation;the proposed braking energy utilization scheme has certain advantages on energy recovery and DC bus voltage stabilization compared with other single-form schemes;the proposed power management strategy can correctly allocate the reference power of each system with a lower construction cost.

关键词： Metro train regenerative braking energy energy feed-back system energy storage system power management