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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 405-414页

作者： Hao liu Fengwei liang Tianyu Hu Jichao Hong Huimin Ma School of Computer and Communication Engineering University of Science and Technology BeijingBeijingChina School of Mechanical Engineering University of Science and Technology BeijingBeijingChina IEEE

Accurate prediction of the state-of-charge(SOC)of battery energy storage system(BESS)is critical for its safety and lifespan in electric *** overcome the imbalance of existing methods between multi-scale feature fusion and global feature extraction,this paper introduces a novel multi-scale fusion(MSF)model based on gated recurrent unit(GRU),which is specifically designed for complex multi-step SOC prediction in practical *** correlation analysis is first employed to identify SOC-related *** parameters are then input into a multi-layer GRU for point-wise feature ***,the parameters undergo patching before entering a dual-stage multi-layer GRU,thus enabling the model to capture nuanced information across varying time ***,by means of adaptive weight fusion and a fully connected network,multi-step SOC predictions are *** extensive validation over multiple days,it is illustrated that the proposed model achieves an absolute error of less than 1.5%in real-time SOC prediction.

关键词： Electric vehicle battery energy storage system(BESS) state-of-charge(SOC)prediction gated recurrent unit(GRU) multi-scale fusion(MSF).

Enhancement of ionic conductivity and fracture toughness by infiltrating porous Li_(0.33)La_(0.56)TiO_(3) pellets

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Journal of Rare Earths 2024年第2期42卷 392-398,I0006页

作者： Xiaojuan Lu Mingyang Duan Jingyu Xiang Yuning liang Songtao liu Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science and EngineeringNorth China Electric Power UniversityBaoding071003China

Although solid-state lithium electrolytes have the potential to reduce the safety issues associated with organic liquid electrolytes,disadvantages such as low total conductivity,large interface impedance,and delamination of the interface due to cyclic stress still need to be *** solid-state lithium-ion conductor Li_(0.33)La_(0.56)TiO_(3)(LLTO) was prepared via a hydrothermal route by using CTAB as templates in this *** LLTO with micro-porous channels was obtained and the total conductivity is comparable to the non-porous *** LLTO pellets are infiltrated with the non-porous LLTO precursor solution,and the total conductivities of the infiltrated porous LLTO are all higher than those without *** infiltration,the porous LLTO calcined at 600℃ achieves the highest total conductivity,7.88×10^(-5) S/*** fracture toughness of the infiltrated LLTO is higher than that of the non-porous *** results demonstrate a new way to prepare solid-state lithium-ion conductors with high ionic conductivity and great tolerance to cyclic stress.

关键词： Perovskite Porous material Infiltration Ionic conductors Fracture toughness Rare earths

Transient state analysis of a rub-impact rotor system during maneuvering flight

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Chinese Journal of Aeronautics 2024年第7期37卷 236-251页

作者： Jun WANG Yunfei liu Zhaoye QIN liang MA Fulei CHU Beijing Key Laboratory of Health Monitoring and Self-Recovery for High-End Machinery Equipment Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

Maneuvering flight substantially affects the dynamic behavior of rotors;particularly,such flight may cause rubbing between a rotor and stator,which is one of the most serious damages in aircraft *** this paper,a nonlinear dynamic model for describing the dynamic characteristics of a rub-impact rotor system during maneuvering flight is established based on the Lagrange ***,numerical simulations employing the Newmark method are performed,delving into the detailed discussion of the influence of parameters such as rotational speed and maneuvering flight on the transient and steady-state responses of the rotor *** effect mechanism of maneuver load and its coupling with rub impact is *** results show that the impact response induced by maneuvering flight is more obvious in the subcritical state than in the supercritical *** additional stiffness and damping are also induced;in particular,the additional damping has a coupling ***,the rub impact imposes an additional constraint on the rotor system,thereby weakening the influence of the maneuver load and becoming the major factor that determines the dynamic behavior of the rotor system at high speeds.

关键词： Maneuvering flight Rub impact Rotor system Dynamic response Impact response

MP-3 microperimeter in early primary open angle glaucoma with a new pattern

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 861-868页

作者： Shuang liang Li-Tao Wang Xiao-Li liu Jia-liang Duan Dan-Yan liu Department of Ophthalmology of the Second Hospital of Hebei Medical University Shijiazhuang 050000Hebei ProvinceChina Department of Ophthalmology Shijiazhuang People’s HospitalShijiazhuang 050000Hebei ProvinceChina

AIM:To investigate macular microperimetry in patients with early primary open angle glaucoma(POAG)using a new custom-made pattern,and analyze the characteristics of macular ***:This case-control study included 38 patients with POAG,who were divided into pre-perimetric glaucoma(18 eyes of 18 patients),early-stage(20 eyes of 20 patients),and control(20 eyes of 20 patients)*** subjects underwent standard 24-2 humphrey visual field *** MP-3 microperimeter with a new custom-made pattern(28 testing points distributed in four quadrants,covering the central 10°of the retina)was used to evaluate macular *** cell complex(GCC)thicknesses were examined using an RS-3000 Advance OCT *** features of structure and function were analysed per ***:The pre-perimetric glaucoma group had significantly lower inferior hemifield macular sensitivity compared to controls(P<0.05).The early-stage POAG group had significantly lower average,inferior hemifield,inferonasal,and inferotemporal mean sensitivities compared to the pre-perimetric glaucoma group(P<0.05),and lower macular sensitivity in all sectors compared to controls(P<0.05).Regarding GCC thickness,all sectors in the early-stage POAG group became thinner compared to those in controls(P<0.05);whereas all sectors in the early-stage POAG group,except the superonasal quadrant,became thinner compared to those in the pre-perimetric glaucoma group(P<0.05).Macular sensitivity and GCC thickness were significantly associated in each *** inferotemporal quadrant had the highest correlation coefficients(0.840).The structure-function relationship for the inferonasal and inferotemporal sectors was stronger compared to the corresponding superior ***:Microperimetry reveals variations in macular sensitivity in patients with early glaucoma earlier than conventional perimetry,particularly in pre-perimetric glaucoma cases in which it might be undetectable by conventional me

关键词： early primary open angle glaucoma macular sensitivity microperimetry optical coherence tomography ganglion cell complex

Influence of Ultra Fine Glass Powder on the Properties and Microstructure of Mortars

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Fluid Dynamics & Materials Processing 2024年第5期20卷 915-938页

作者： Wei Chen Dingdan liu Yue liang School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China

This study focuses on the effect of ultrafine waste glass powder on cement strength,gas permeability and pore *** contents were considered,with particle sizes ranging from 2 to 20μ***,alkali activation was considered to ameliorate the reactivity and cementitious properties,which were assessed by using scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),and specific surface area pore size distribution *** to the results,without the addition of alkali activators,the performance of glass powder mortar decreases as the amount of glass powder increases,affecting various aspects such as strength and resistance to gas *** 5%glass powder mortar demonstrated a compressive strength at 60 days higher than that of the control ***,adding alkali activator(CaO)during hydration ameliorated the hydration environment,increased the alkalinity of the composite system,activated the reactivity of glass powder,and enhanced the interaction of glass powder and pozzolanic *** general,compared to ordinary cement mortar,alkali-activated glass powder mortar produces more hydration products,showcases elevated density,and exhibits improved gas ***,alkali-activated glass powder mortar demonstrates an improvement in performance across various aspects as the content *** a substitution rate of 15%,the glass powder mortar reaches its optimal levels of strength and resistance to gas permeability,with a compressive strength increase ranging from 28.4%to 34%,and a gas permeation rate reduction between 51.8%and 66.7%.

关键词： Mortar waste glass powder alkali activation compressive strength gas permeability pore structure

An Investigation into the Compressive Strength,Permeability and Microstructure of Quartzite-Rock-Sand Mortar

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Fluid Dynamics & Materials Processing 2024年第4期20卷 859-872页

作者： Wei Chen Wuwen liu Yue liang School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China

River sand is an essential component used as a fine aggregate in mortar and *** to unrestrained exploitation,river sand resources are gradually being *** requires alternative *** study deals with the properties of cement mortar containing different levels of manufactured sand(MS)based on quartzite,used to replace river *** river sand was replaced at 20%,40%,60%and 80%with MS(by weight or volume).The mechanical properties,transfer properties,and microstructure were examined and compared to a control group to study the impact of the replacement *** results indicate that the compressive strength can be improved by increasing such a *** strength was improved by 35.1%and 45.5%over that of the control mortar at replacement levels of 60%and 80%,*** there was a weak link between porosity and gas permeability in the mortars with manufactured sand,the gas permeability decreased with growing the replacement *** microstructure of the MS mortar was denser,and the cement paste had fewer microcracks with increasing the replacement level.

关键词： Manufactured sand quartzite compressive strength gas permeability microstructure

Effect of land use on soil nematode community composition and co-occurrence network relationship

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Journal of Integrative Agriculture 2024年第8期23卷 2807-2819页

作者： Xiaotong liu Siwei liang Yijia Tian Xiao Wang Wenju liang Xiaoke Zhang Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China Tillage and Cultivation Research Institute Liaoning Academy of Agricultural SciencesShenyang 110161China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Conservation Tillage and Ecological Agriculture in Liaoning Province Shenyang 110016China

Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and *** characterize the effect of land use on soil biota,soil nematode communities in crop land,forest land and fallow land were investigated in six regions of northern *** richness,diversity,abundance and biomass of soil nematodes was the lowest in crop *** richness and diversity of soil nematodes were 28.8and 15.1%higher in fallow land than in crop land,*** significant differences in soil nematode indices were found between forest land and fallow land,but their network keystone genera composition was *** the keystone genera,50%of forest land genera were omnivores-predators and 36%of fallow land genera were *** proportion of fungivores in forest land was 20.8%lower than in fallow *** network complexity and the stability were lower in crop land than forest land and fallow *** pH,NH_(4)^(+)-N and NO_(3)^(–)-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest *** nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow *** use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera.

关键词： soil nematode trophic groups community composition co-occurrence network land use

Engineering Fronts 2023 announced engineering fronts in fields of Energy and Electrical Science and Technology

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Frontiers in Energy 2024年第1期18卷 4-7页

作者： Ruiqin liu liang YIN Lingxiao FU Editorial Office of Frontiers in Energy Shanghai Jiao Tong UniversityShanghai 200240China

1 Introduction An engineering front refers to important directions that have a significant impact on and lead the future innovation of engineering science and *** is characterized by its forward looking,leading,and exploratory *** 2017,the Chinese Academy of Engineering(CAE)has annually organized a project known as“Global Engineering Fronts,”identifying and releasing engineering research fronts and engineering development fronts,tracking the trends in engineering science and technology,and actively guiding the academic development and promoting innovation in engineering science and technology.

关键词： technology. annually looking

An improved GNSS ambiguity best integer equivariant estimation method with Laplacian distribution for urban low-cost RTK positioning

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Satellite Navigation 2024年第1期5卷 109-124页

作者： Ying liu Wanke liu Xiaohong Zhang Yantao liang Xianlu Tao Liye Ma School of Geodesy and Geomatics Hubei Luojia LaboratoryWuhan University129 Luoyu RoadWuhan430079HubeiChina Chinese Antarctic Center of Surveying and Mapping Wuhan University129 Luoyu RoadWuhan430079HubeiChina School of Instrument Science and Engineering Southeast UniversityNanjingJiangsuChina The 54 Research Institute of China Electronics Technology Group CorporationShijiazhuang050081HebeiChina State Key Laboratory of Satellite Navigation System and Equipment Technology Shijiazhuang050081HebeiChina

The integer least squares(ILS)estimation is commonly used for carrier phase ambiguity resolution(AR).More recently,the best integer equivariant(BIE)estimation has also attracted an attention for complex application scenarios,which exhibits higher reliability by a weighted fusion of integer ***,traditional BIE estimation with Gaussian distribution(GBIE)faces challenges in fully utilizing the advantages of BIE for urban low-cost positioning,mainly due to the presence of outliers and unmodeled *** this end,an improved BIE estimation method with Laplacian distribution(LBIE)is proposed,and several key issues are discussed,including the weight function of LBIE,determination of the candidates included based on the OIA test,and derivation of the variance of LBIE solutions for reliability *** results show that the proposed LBIE method has the positioning accuracy similar to the BIE using multivariate t-distribution(TBIE),and significantly outperforms the ILS-PAR and GBIE *** an urban expressway test with a Huawei Mate40 smartphone,the LBIE method has positioning errors of less than 0.5 m in three directions and obtains over 50%improvements compared to the ILS-PAR and GBIE *** an urban canyon test with a low-cost receiver STA8100 produced by STMicroelectronics,the positioning accuracy of LBIE in three directions is 0.112 m,0.107 m,and 0.252 m,respectively,with improvements of 17.6%,27.2%,and 26.1%compared to GBIE,and 23.3%,28.2%,and 30.6%compared to ***,its computational time increases by 30–40%compared to ILS-PAR and is approximately half of that using TBIE.

关键词： Ambiguity resolution Best integer equivariant estimation Laplacian distribution Urban environments Low-cost GNSS receivers Real-time kinematic

Analysis and Modeling of Time Output Characteristics for Distributed Photovoltaic and Energy Storage

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Energy Engineering 2024年第4期121卷 933-949页

作者： Kaicheng liu Chen liang Xiaoyang Dong Liping liu China Electric Power Research Institute Beijing100192China Electric Power Research Institute State Grid Gansu Electric Power CompanyLanzhou730000China State Key Laboratory of Power Grid Safety Beijing100084China

Due to the unpredictable output characteristics of distributed photovoltaics,their integration into the grid can lead to voltage fluctuations within the regional power ***,the development of spatial-temporal coordination and optimization control methods for distributed photovoltaics and energy storage systems is of utmost importance in various *** paper approaches the issue from the perspective of spatiotemporal forecasting of distributed photovoltaic(PV)generation and proposes a Temporal Convolutional-Long Short-Term Memory prediction model that combines Temporal Convolutional Networks(TCN)and Long Short-Term Memory(LSTM).To begin with,an analysis of the spatiotemporal distribution patterns of PV generation is conducted,and outlier data is handled using the 3σ ***,a novel approach that combines temporal convolution and LSTM networks is introduced,with TCN extracting spatial features and LSTM capturing temporal ***,a real spatiotemporal dataset from Gansu,China,is established to compare the performance of the proposed network against other *** results demonstrate that the model presented in this paper exhibits the highest predictive accuracy,with a single-step Mean Absolute Error(MAE)of 1.782 and an average Root Mean Square Error(RMSE)of 3.72 for multi-step predictions.

关键词： Photovoltaic power generation spatio-temporal prediction temporal convolutional network long short-term memory network