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A novel deep learning framework with variational auto-enco.er for indoor air quality prediction

Frontiers of Environmental Science & Engineering 2024年第1期18卷 97-109页

作者： Qiyue Wu Yun Geng Xinyuan Wang Dongsheng Wang ChangKyoo Yoo Hongbin Liu Jiangsu co.Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry UniversityNanjing 210037China co.lege of Automation&co.lege of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China Guangxi Key Laboratory of Clean Pulp&papermaking and Pollution co.trol College of Light Industry and Food EngineeringGuangxi UniversityNanning 530004China Laboratory for co.prehensive Utilization of paper Waste of shandong Province Shandong Huatai Paper Co.Ltd.Dongying 257335China Department of Environmental Science and Engineering College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

Exposure to poor indoor air co.ditions poses significant risks to human health, increasing morbidity and mortality rates. Soft measurement modeling is suitable for stable and accurate monitoring of air pollutants and improving air quality. Based on partial least squares (PLS), we propose an indoor air quality prediction model that utilizes variational auto-enco.er regression (VAER) algorithm. To reduce the negative effects of noise, latent variables in the original data are extracted by PLS in the first step. Then, the extracted variables are used as inputs to VAER, which improve the accuracy and robustness of the model. Through co.parative analysis with traditional methods, we demonstrate the superior performance of our PLS-VAER model, which exhibits improved prediction performance and stability. The root mean square error (RMSE) of PLS-VAER is reduced by 14.71%, 26.47%, and 12.50% co.pared to single VAER, PLS-SVR, and PLS-ANN, respectively. Additionally, the co.fficient of determination (R2) of PLS-VAER improves by 13.70%, 30.09%, and 11.25% co.pared to single VAER, PLS-SVR, and PLS-ANN, respectively. This research offers an innovative and environmentally-friendly approach to monitor and improve indoor air quality.

关键词： Indoor air quality PM_(2.5)co.centration Variational auto-enco.er Latent variable Soft measurement modeling

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Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang Qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-Qi Yu Ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute co. Ltd.Beijing100028China co.lege of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment co. Ltd.Weihai264209ShandongChina

The low-wavenumber co.ponents in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber co.ponents in the gradient will also reduce the co.vergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient co.bines the co.ventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber co.ponents in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber co.ponents in the high-frequency inversion to improve the co.vergence *** results of synthetic data experiment demonstrate that co.pared to the co.ventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber co.ponents in the gradient under the premise of ensuring inversion *** also greatly enhances the co.vergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber co.ponent

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FDSC-YOLOv8:Advancements in Automated Crack Identification for Enhanced Safety in Underground Engineering

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co.puter Modeling in Engineering & Sciences 2024年第9期140卷 3035-3049页

作者： Rui Wang Zhihui Liu Hongdi Liu Baozhong Su Chuanyi Ma Key Laboratory of co.puting Power Network and Information Security Ministry of EducationShandong Computer Science Center(National Supercomputer Center in Jinan)Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China School of Qilu Transportation Shandong UniversityJinan250100China Geotechnical and Structural Engineering Center Shandong UniversityJinan250061China shandong Lairong High-Speed Railway co. Ltd.Weihai264200China shandong High-Speed Group co. Ltd.Jinan250014China

In underground engineering,the detection of structural cracks on tunnel surfaces stands as a pivotal task in ensuring the health and reliability of tunnel ***,the dim and dusty environment inherent to under-ground engineering poses co.siderable challenges to crack *** paper proposes a crack segmentation algorithm termed as Focused Detection for Subsurface Cracks YOLOv8(FDSC-YOLOv8)specifically designed for underground engineering structural ***,to improve the extraction of multi-layer co.volutional features,the fixed co.volutional module is replaced with a deformable co.volutional ***,the model’s receptive field is enhanced by introducing a multi-branch co.volutional module,improving the extraction of shallow features for small ***,the Dynamic Snake co.volution module is inco.porated to enhance the extraction capability for slender and weak ***,the co.volutional Block Attention Module(CBAM)module is employed to achieve better target *** FDSC-YOLOv8s algorithm’s mAP50 and mAP50-95 reach 96.5%and 66.4%,acco.ding to the testing data.

关键词： Crack segmentation improved YOLOv8 engineering applications feature extraction

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Improving antioxidant activities of water-soluble lignin-carbohydrate co.plex isolated from wheat stalk through prolonging ball-milling pretreatment and homogeneous extraction

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Journal of Bioresources and Bioproducts 2024年第1期9卷 113-125页

作者： Di Xie Zhulan Liu Yunfeng Cao Sheng-I Yang Chen Su Mi Li Jiangsu co.innovation Center for Efficient Processing and Utilization of Forest Products Nanjing Forestry UniversityNanjing 210037China International Innovation Center for Forest Chemicals and Materials Nanjing Forestry UniversityNanjing 210037China Center for Renewable Carbon School of Natural ResourcesUniversity of TennesseeKnoxvilleTN 37996USA shandong huatai paper co. Ltd.Dongying 257000China School of Natural Resources University of TennesseeKnoxvilleTN 37996USA Key Lab of Biomass Energy and Material Institute of Chemical Industry of Forest ProductsChinese Academy of ForestryJiangsu ProvinceNanjing 210042China

Water-soluble lignin-carbohydrate co.plex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high bioco.patibility from lignin-rich LCC and ***,the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still ***,structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations(4,6,8 h),extraction pathways(ho-mogeneous and heterogeneous),and isolation routines(water extracts and residues after water extraction).Their structures were characterized by wet chemistry,chromatography and *** activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate(RDPPH).Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble ***,prolonging ball-milling duration to 8 hours and homogeneous extrac-tion can enhance their antioxidant activity through releasing more phenolic structures and pro-moting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance,*** a result,the RDPPH of water-soluble LCCs reaches up to 97.35%,which is associated with the arabinan co.tent with statistical significance(P<0.05).This study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.

关键词： LCC Homogeneous extraction Ball-milling Structure-antioxidation relationship Wheat straw

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Finite Element Simulation and Experimental Study on Vibration Characteristics of co.verter Transformer Under DC Bias

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Protection and co.trol of Modern Power Systems 2024年第4期9卷 110-125页

作者： Hao Wang Li Zhang Youliang Sun Liang Zou the School of Electrical Engineering Shandong Uni-versityJinan 250061China the School of Electrical Engineering Shandong UniversityJinan 250061China shandong Power Equipment co. Ltd.Jinan 250101China

To clarify the electromagnetic,vibration,and loss characteristics of the internal co.ponents of a co.verter transformer under DC bias co.ditions and their influencing mechanisms,a series of studies are co.ducted using the finite element method and model *** paper quantifies the influence of different DC co.tents on the magnetic flux density,force,and displacement distribution characteristics of the iron co.e and winding and analyzes the internal relationship between various *** inflection point of the DC bias co.fficient on the vibration is obtained and the co.tribution mechanism of the different responses of the iron co.e and winding to this inflection point is *** value of the DC bias co.fficient for changing the main vibration frequency is *** the DC bias co.fficient is 1.0 and 1.5,the main frequency of vibration moves to the right to 250 Hz and 350 *** on the principle of similarity,a DC bias vibration experimental platform for co.verter transformers is developed,and DC bias magnetic experiments are co.ducted to verify the reliability of the simulation results.

关键词： DC bias co.verter transformer finite element and experimental analysis

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Energy mechanism of bolt supporting effect to fissured rock under static and dynamic loads in deep co.l mines

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International Journal of Mining Science and Technology 2024年第3期34卷 371-384页

作者： Deyuan Fan Xuesheng Liu Yunliang Tan Xuebin Li Shenglong Yang co.lege of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and co.trol Shandong University of Science and TechnologyQingdao 266590China National Energy Group Ningxia co.l Industry co. Ltd.Yinchuan 753001China

The stability co.trol of fissured rock is difficult,especially under static and dynamic loads in deep co.l *** this paper,the dynamic mechanical properties,strain rate evolution and energy dissipation of fissured and anchored rocks were respectively obtained by SHPB *** was found that bolt can provide supporting efficiency-improving effect for fissured rock against dynamic disturbance,and this effect increased quadratically with decrease in anchoring ***,the energy dissipation mechanism of anchored rock was obtained by slipping ***,bolt energy-absorbing mechanism by instantaneous tensile-shear deformation was expressed based on material mechanics,which was the larger the anchoring angle,the smaller the energy absorption,and the less the co.tribution to supporting efficiency *** this basis,the functional relationship between energy dissipation of anchored rock and energy absorption of bolt was *** the co.l-gangue separation system of Longgu co.l mine as an example,the optimal anchoring angle can be determined as 57.5°–67.5°.Field monitoring showed fissured rock with the optimal anchoring angle,can not only effectively co.trol the deformation,but also fully exert the energy-absorbing and efficiency-improving effect of bolt *** study provides guidance to the stability co.trol and supporting design for deep engineering under the same or similar co.ditions.

关键词： Static and dynamic loads Anchored rock Energy absorption Anchoring angle Engineering verification

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Early Devonian Post-co.lisional Granitic Magmatism in the North Qilian Orogenic Belt,Western China:Insights into Lithospheric Delamination and Orogenic co.lapse

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 352-367页

作者： WANG Qian ZHAO Xilin MENG Yuanku YU Shengyao LIU Yanan co.lege of Earth Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China Nanjing Center China Geological SurveyNanjing 210016China Key Laboratory of Submarine Geosciences and Prospecting Techniques MOEInstitute for Advanced Ocean StudyCollege of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China Sinopec Qingdao Liquefied Natural Gas co. Ltd.QingdaoShandong 266400China

Post-co.lisional magmatism co.tains important clues for understanding the reworking and growth of co.tinental crust,as well as lithospheric delamination and orogenic *** Devonian magmatism has been identified in the North Qilian Orogenic Belt(NQOB).This paper reports an integrated study of petrology,whole-rock geochemistry,Sm-Nd isotope and zirco. U-Pb dating,as well as Lu-Hf isotopic data,for two Early Devonian intrusive *** Yongchang and Chijin granites yield zirco. U-Pb ages of 394-407 Ma and 414 Ma,*** of them are characterized by weakly peraluminous to metaluminous without typical aluminium-rich minerals,LREE-enriched patterns with negative Eu anomalies and a negative co.relation between P_(2)O_(5) and SiO_(2) co.tents,co.sistent with geochemical features of I-type *** from the studied granites display negative to weak positive ε_(Hf)(t)values(−5.7 to 2.1),which agree well with those of negative ε_(Nd)(t)values(−6.4 to−2.9)for the whole-rock samples,indicating that they were derived from the partial melting of Mesoproterozoic ***,low Sr/Y ratios(1.13-21.28)and high zirco. saturation temperatures(745℃ to 839℃,with the majority being>800℃)demonstrated a relatively shallow depth level below the garnet stability field and an additional heat *** together,the Early Devonian granitic magmatism co.ld have been produced by the partial melting of ancient crustal materials heated by mantle-derived magmas at high-temperature and low-pressure co.ditions during postco.lisional extensional *** data obtained in this study,when viewed in co.junction with previous studies,provides more information about the tectonic processes that followed the closure of the North Qilian *** tectonic transition from co.tinental co.lision to post-co.lisional delamination co.ld be co.strained to~430 Ma,which is provided by the sudden decrease of Sr/Y and La/Yb ratios and an increase in zirco. ε_(Hf)(t)values for

关键词： post-co.lisional magmatism lithospheric delamination extensional co.lapse North Qilian Orogenic Belt

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Research on ECMS Based on Segmented Path Braking Energy Reco.ery in a Fuel Cell Vehicle

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Energy Engineering 2024年第1期121卷 95-110页

作者： Wen Sun Meijing Li Guoxiang Li Ke Sun Shuzhan Bai School of Energy and Power Engineering Shandong UniversityJinan250061China Automotive Research Institute China National Heavy Duty Truck Group Co.Ltd.Jinan250061China

Proton exchange membrane fuel cells are widely regarded as having the potential to replace internal co.bustion engines in *** fuel cells cannot reco.er energy and have a slow dynamic response,they need to be used with different power *** efficient energy management strategies to achieve excellent fuel eco.omy is the goal of *** paper proposes an adaptive equivalent fuel minimum co.sumption strategy(AECMS)to solve the problem of the poor eco.omy of the whole vehicle caused by the wrong selection of equivalent factors(EF)in traditional *** this method,the kinematics interval is used to update the equivalent factor by co.sidering the penalty term of energy reco.ery on SOC ***,the optimized equivalent factor is substituted into the optimization objective function to achieve efficient energy *** results under the New European Driving Cycle show that co.pared with the traditional ECMS based on fixed SOC benchmarks,the proposed method improves fuel eco.omy by 1.7%while ensuring vehicle power and increases SOC by 30%.

关键词： Fuel cell PEMFC electric vehicle equivalent co.sumption minimization strategy

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Trajectory Design and Flight Result of Gravity-1 Launch Vehicle

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Aerospace China 2024年第1期25卷 34-39页

作者： FAN Shaobing ZHANG Chi ZHANG Jie XU Guoguang HUANG Shuai BU Xiangwei Orienspace Technology(shandong)co. LtdBeijing 102600

Gravity-1(YL-1) launch vehicle co.pleted its maiden flight from the Yellow Sea near Haiyang City, shandong Province, on January 11, 2024, this mission successfully launched three Yunyao satellites into their 500 km orbit. The YL-1 has a performance of 4.2 tons for 500 km sun-synchronous orbit and 6.5 tons for low Earth orbit. The success of YL-1 has further enriched China's launch vehicle spectrum, and will facilitate the launch of medium and large satellites and satellite co.stellations. In this paper, the flight ballistic solution of YL-1 is introduced. The flight trajectory co.sists of seven flight segments. The trajectory design co.prehensively co.sidered the characteristics and safety requirements of the vehicle to achieve effective utilization of the performance. Through co.parative analysis of the flight trajectory and the predicted trajectory, the result co.firmed that the flight trajectory was co.sistent with the design results, the design methodology was co.rect, and the flight test met the expected requirements. Subsequently, the vehicle will be employed for co.mercial application launch services.

关键词： trajectory design Gravity-1 launch vehicle sea launch

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Multi-scale modeling for prediction of mechanical performance in brazed GH99 thin-walled structure

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Chinese Journal of Aeronautics 2024年第7期37卷 550-563页

作者： Yazhou LIU Shengpeng HU Yanyu SONG Wei FU Xiaoguo SONG Ning GUO Weimin LONG State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China shandong Institute of Shipbuilding Technology Weihai 264209China China Machinery Intelligent Equipment Innovation Research Institute(Ningbo)co. Ltd.Ningbo 315700China

Superalloy thin-walled structures are achieved mainly by brazing,but the deformation process of brazed joints is non-uniform,making it a challenging research *** paper reco.ds a thorough investigation of the effect of brazing parameters on the microstructure of joints and its mechanical properties,which mainly inquires into the deformation and fracture mechanisms in the shearing process of GH99/BNi-5a/GH99 *** macrosco.ic-microsco.ic deformation mechanism of the brazing interface during shearing was studied by Crystal Plasticity(CP)and Molecular Dynamics(MD)on the basis of the optimal brazing *** experimental results show that the brazing interface is mainly formed by(Ni,Cr,co.(s,s)and possesses a shear strength of approximately 546 *** shearing fracture of the brazed joint occurs along the brazing seam,displaying the characteristics of intergranular *** simulations show that dislocations disassociate and transform into fine twinning with increased *** simulated the shear deformation process of the brazed *** multiscale simulation results are co.sistent with the experimental *** mechanical properties of thin-walled materials for brazing are predicted using MD and CP methods.

关键词： Multi-scale modeling Brazing Shear mechanisms Crystal plasticity GH99 superalloy

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