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Determination of the Pile Drivability Using Random Forest Optimized by Particle Swarm Optimization and Bayesian Optimizer

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 871-892页

作者： Shengdong Cheng Juncheng gao Hongning qi State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an710048China School of Resources and Safety Engineering Central South UniversityChangsha410083China

Driven piles are used in many geological environments as a practical and convenient structural ***,the determination of the drivability of piles is actually of great importance in complex geotechnical *** methods of predicting pile drivability often rely on simplified physicalmodels or empirical formulas,whichmay lack accuracy or applicability in complex geological ***,this study presents a practical machine learning approach,namely a Random Forest(RF)optimized by Bayesian Optimization(BO)and Particle Swarm Optimization(PSO),which not only enhances prediction accuracy but also better adapts to varying geological environments to predict the drivability parameters of piles(i.e.,maximumcompressive stress,maximum tensile stress,and blow per foot).In addition,support vector regression,extreme gradient boosting,k nearest neighbor,and decision tree are also used and applied for comparison *** order to train and test these models,among the 4072 datasets collected with 17model inputs,3258 datasets were randomly selected for training,and the remaining 814 datasets were used for model ***,the results of these models were compared and evaluated using two performance indices,i.e.,the root mean square error(RMSE)and the coefficient of determination(R2).The results indicate that the optimized RF model achieved lower RMSE than other prediction models in predicting the three parameters,specifically 0.044,0.438,and 0.146;and higher R^(2) values than other implemented techniques,specifically 0.966,0.884,and *** addition,the sensitivity and uncertainty of the optimized RF model were analyzed using Sobol sensitivity analysis and Monte Carlo(MC)*** can be concluded that the optimized RF model could be used to predict the performance of the pile,and it may provide a useful reference for solving some problems under similar engineering conditions.

关键词： Random forest regression model pile drivability Bayesian optimization particle swarm optimization

Efficient and robust CNN-LSTM prediction of flame temperature aided light field online tomography

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Science China(Technological Sciences) 2024年第1期67卷 271-284页

作者： NIU ZhiTian qi Hong SUN AnTai REN YaTao HE MingJian gao BaoHai School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Aerospace Thermophysics Ministry of Industry and Information TechnologyHarbin 150001China

Light field tomography,an optical combustion diagnostic technology,has recently attracted extensive attention due to its easy implementation and ***,the conventional iterative methods are high data throughput,low efficiency and time-consuming,and the existing machine learning models use the radiation spectrum information of the flame to realize the parameter field measurement at the current *** is still an offline measurement and cannot realize the online prediction of the instantaneous structure of the actual turbulent combustion *** this work,a novel online prediction model of flame temperature instantaneous structure based on deep convolutional neural network and long short-term memory(CNN-LSTM)is *** method uses the characteristics of local perception,shared weight,and pooling of CNN to extract the threedimensional(3D)features of flame temperature and outgoing radiation ***,the LSTM is used to comprehensively utilize the ten historical time series information of high dynamic combustion flame to accurately predict 3D temperature at three future moments.A chaotic time-series dataset based on the flame radiation forward model is built to train and validate the performance of the proposed CNN-LSTM *** is proven that the CNN-LSTM prediction model can successfully learn the evolution pattern of combustion flame and make accurate predictions.

关键词： temperature prediction convolutional neural network long short-term memory light field imaging online tomography

Constructing hierarchical arrays with core-shell metal oxides@metal coordination polymers for efficient and stable overall water splitting

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Nano Research 2024年第6期17卷 4882-4888页

作者： Shuai qi Jinlian Liao Kunzhong Chen Senkai Li Jinwen Zhao Tianchi Huang Na meng Hengpan Yang qi Hu Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Developing non-precious metal-based bifunctional electrocatalysts capable for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is essential to achieve efficient water electrolysis for mass hydrogen production,however it remains ***,we report the synthesis of hierarchical nanorod arrays comprising core-shell structured P-doped NiMoO4@NiFe-coordination polymer(denoted as P-NiMoO4@NiFeCP)as bifunctional electrocatalysts for water ***,we systematically investigate the influence of NiFeCP shell thickness on electrocatalytic activity,manifesting the presence of strong interfacial synergetic effect between P-NiMoO4 and NiFeCP for boosting both the HER and *** advantageous hierarchical architectures and unique core-shell structures,optimized P-NiMoO_(4)@NiFeCP-7.3(7.3 is the shell thickness in nm)requires overpotentials of merely 256 and 297 mV to yield a current density of 1000 mA·cm^(−2)for the HER and OER in 1 M KOH,*** importantly,it can serve as a bifunctional electrocatalyst for efficient and sustainable overall water electrolysis,delivering large current densities of 500 and 1000 mA·cm^(−2)at low cell voltages of 1.804 and 1.865 V,along with high stability of over 500 h at 1000 mA·cm−2,demonstrating the great potential of this electrocatalyst towards practical applications.

关键词： hydrogen evolution reaction oxygen evolution reaction overall water splitting non-precious metal-based electrocatalysts core-shell structures

Highly Red Emissive Conjugated Homopolymers Based on Double B←N Bridged Bipyridine Unit

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Chinese Journal of Polymer Science 2024年第8期42卷 1029-1037页

作者： Yu-Yue gao Kai-Yuan Zhang Shu-meng Wang Hui Tong Jun Liu State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Conjugated homopolymers based on six-member rings,e.g.,polyfluorene,always exhibit blue emission and conjugated homopolymers based on five-member rings,e.g.,polythiophene,can give red emission with low *** this work,we report a series of new conjugated homopolymers based on six-member rings with high-efficiency deep-red *** repeating units of the red light emitting homopolymers are double B←N bridged bipyridine(BNBP)with the boron atoms functionalized with diphenyl,borafluorene,and 2,7-di-tert-butyl-borafluorene groups,*** relationship between the chemical structures and the opto-electronic properties of the monomers and the homopolymers has been systematically *** three polymers emit pure red light(λ_(max)=656 nm)or deep red light(λ_(max)=693 nm)with fluorescence quantum efficiency in solution higher than 60%.The polymers can be used as the emitters in solution-processed organic light-emitting diodes with red emission and decent device *** work indicates a new strategy to design highly efficient light emitting conjugated polymers.

关键词： Conjugated homopolymers Double B←N bridged bipyridine(BNBP) Deep-red emission High fluorescent efficiency

Early-onset and later-onset cancer:trends,risk factors,and prevention in Northern China

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Science China(Life Sciences) 2024年第9期67卷 1928-1940页

作者： Tong Liu Chen-An Liu qing-Song Zhang qi Zhang Yi-Ming Wang meng-meng Song Shi-qi Lin Li Deng Shou-Ling Wu Han-Ping Shi Department of Gastrointestinal Surgery Department of Clinical NutritionBeijing Shijitan HospitalCapital Medical UniversityBeijing 100038China National Clinical Research Center for Geriatric Diseases Xuanwu HospitalCapital Medical UniversityBeijing 100053China Key Laboratory of Cancer FSMP for State Market Regulation Beijing 100038China Laboratory for Clinical Medicine Capital Medical UniversityBeijing 100038China Department of General Surgery Kailuan General HospitalTangshan 063000China Department of Genetics Yale School of MedicineNew Haven 06510USA Department of Hepatobiliary Surgery Kailuan General HospitalTangshan 063000China Cardiovascular Research Institute University of CaliforniaSan Francisco 94158USA Department of Cardiology Kailuan General HospitalTangshan 063000China

The characteristics of early-onset(onset age<50 years)and later-onset(onset age≥50 years)cancers differ *** novel risk factors for both types of cancer is crucial for increasing awareness of cancer prevention and for reducing its *** study aimed to analyze the trends in incidence and risk factors for early-onset and late-onset *** conducted a prospective study by drawing data from the Kailuan *** study included 6,741 participants with cancer(624 with early-onset cancer and 6,117 with later-onset cancer)and 6,780 matched controls among the 186,249 participants who underwent Kailuan health examinations from 2006 to *** primary outcomes were cancer incidence rates,and associated risk factors for early-and later-onset *** Cox regression was used to calculate hazard ratios and 95% confidence intervals of each exposure factor for early-and later-onset cancer by cancer *** risk proportions were used to estimate the number of cases that could be prevented by eliminating a risk factor from the *** for liver cancer,incidence rates for nearly all types of cancer increased during the study ***,alcohol consumption,lipid metabolism disorders,hypertension,diabetes mellitus,fatty liver,and inflammation were associated with a significantly increased risk of cancer at multiple sites,but risk factors for cancer incidence differed by ***,alcohol consumption,inflammation,and hypertension were the major contributors to preventable *** incidence of several different types of cancer,including earlyonset cancer,is increasing in northeastern *** in risk factors between early-onset and later-onset malignancies may contribute to the divergence in the observed changes in incidence trends between these two specific types of cancer.

关键词： cancer early-onset later-onset trend risk factor prevention

Synergistic effect of Zr and Mo on precipitation and high-temperature properties of Al-Si-Cu-Mg alloys

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China Foundry 2024年第1期21卷 71-81页

作者： Chao gao Bing-rong Zhang Yin-ming Li Zhi-ming Wang Xiang-bin meng Faculty of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Hebei Ounai Machinery Mould Co.Ltd. Xingtai 054500HebeiChina

This study focuses on finding a solution to the sharp decline in mechanical properties of Al-Si-Cu-Mg alloys due to rapid coarsening of traditional intermediate phases at high temperature.A new type of modified al oy,to be used in automobile engines at high temperatures,was prepared by adding Zr and Mo into Al-Si-Cu-Mg *** synergistic effects of Zr and Mo on the microstructure evolution and high-temperature mechanical properties were *** show that the addition of Zr and Mo generates a series of intermetallic phases dispersed in the *** can improve the strength of the alloy by hindering dislocation movement and crack *** addition,some nano-strengthened phases show coherent interfaces with the matrix and improve grain *** addition of Mo greatly improves the heat resistance of the *** extremely low diffusivity of Mo enables it to improve the thermal stability of the intermetallic phases,inhibit precipitation during aging,reduce the size of the precipitates,and improve the heat resistance of the alloy.

关键词： Al-Si-Cu-Mg alloy high-temperature properties Zr-Mo-rich intermetallics nano-strengthening phases

Particle size characterization and sources of sediments in the Uzhumqin sand dunes

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Journal of Mountain Science 2024年第8期21卷 2631-2645页

作者： ZHANG Hao LIU Yang DANG Xiaohong meng Zhongju LI Shuangli gao Yong Inner Mongolia Agricultural University Inner Mongolia 010018China Inner Mongolia Autonomous Region Water Resources Research Institute Hohhot 010020China

Sediment constitutes the fundamental basis for forming and evolving aeolian *** characteristics of sediment particle size offer insights into the development and evolution of sandy terrain,making their study critical to understanding aeolian geomorphology and sand *** this study,we combined high-density collection of surface sediments in the Uzhumqin sand dunes and GIS spatial analysis to analyze the particle size parameters and changes in the spatial distribution of surface sediments in this *** addition,we used an end-member analysis to identify the potential sources of the *** results showed that surface sediments in the Uzhumqin sand dunes had distinct spatial *** and coarse grain sands dominated the sediments in the dunes,and the mean grain size and the sorting coefficient generally increased along the prevailing wind direction,with high values in individual areas related to factors such as material sources and vegetation *** was strongly influenced by factors such as landform change and human activity,and spatial variability became more *** and the soil fractal dimension showed generally decreasing trends along the prevailing wind *** dune fixation,the contents of clay and powder particles in the soil increased;the mean particle size,the sorting coefficient,and the fractal dimension of the soil gradually increased,and the skewness and kurtosis gradually *** end-member analysis results indicated the existence of five end-members(EM)in the dune *** 1 was a mixed component of wind-deposited fine sands and nearby fluvial *** 2 was the main component of sediments in the study area and was the result of sorting lake sediments by wind action and by the local *** 3 may be a product of river flood *** 4 and EM 5 had coarser grain *** 4 was a lake-phase sediment product influenced by topographic and vegetation cover factors,and EM

关键词： Sediment Particle size Spatial differences End-member analysis Uzhumqin sand dunes

Dual sliding mode coordinated control of manipulator grasping system with visual assistance

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Control Theory and Technology 2024年第1期22卷 106-121页

作者： Pengxin Zhang Haisheng Yu Xiangxiang meng Zhe Li qing Yang Xunkai gao College of Automation Qingdao UniversityQingdao266071ShandongChina Shandong Province Key Laboratory of Industrial Control Technology Qingdao266071ShandongChina

The operation efficiency of the manipulator is placed in the primary position in automatic production. This paper proposes a coordinated control strategy for joint servo and visual servo to enable timely transfer and accurate gripping in the working area. Aiming at the issues of chattering and slow convergence of traditional sliding mode controller, a fast variable power reaching rate on the basis of the non-singular fast terminal sliding mode controller is proposed, which can effectively reduce the convergence time and chattering. For the purpose of addressing the problem that the traditional visual servo control method is sensitive to the environment, a visual servo controller based on integral sliding mode is proposed, to ensure the favorable positioning accuracy of the manipulator. Based on the two proposed controllers mentioned above, a coordinated control strategy is used to implement the control of the manipulator. Finally, the upper computer software is developed using the C# programming language to monitor the workstation. The feasibility of the above-mentioned method is verified through multiple simulations and experiments.

关键词： Automatic production Joint servo Visual servo Coordinated control Non-singular fast terminal sliding mode Integral sliding mode

Quantum dot-enabled infrared hyperspectral imaging with single-pixel detection

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Light(Science & Applications) 2024年第6期13卷 1112-1121页

作者： Heyan meng Yuan gao Xuhong Wang Xianye Li Lili Wang Xian Zhao Baoqing Sun School of Information Sciences and Engineering Shandong UniversityQingdaoChina Center for Optics Research and Engineering(CORE) Key Laboratory of Laser&Infrared System(Shandong University)Ministry of EducationShandong UniversityQingdaoChina School of Mechanical Electrical and Information EngineeringShandong UniversityWeihaiChina

Near-infrared(NIR)hyperspectral imaging is a powerful technique that enables the capture of three-dimensional(3D)spectra-spatial information within the NIR spectral range,offering a wide array of ***,the high cost associated with InGaAs focal plane array(FPA)has impeded the widespread adoption of NIR hyperspectral *** this challenge,in this study,we adopt an alternative approach—single-pixel detection for NIR hyperspectral *** investigation reveals that single-pixel detection outperforms conventional FPA,delivering a superior signal-to-noise ratio(SNR)for both spectral and imaging *** implement this strategy,we leverage self-assembled colloidal quantum dots(CQDs)and a digital micromirror device(DMD)for NIR spectral and spatial information multiplexing,complemented by single-pixel detection for simultaneous spectral and image *** experimental results demonstrate successful NIR hyperspectral imaging with a detection window about 600 nm and an average spectral resolution of 8.6 nm with a pixel resolution of 128×*** resulting spectral and spatial data align well with reference instruments,which validates the effectiveness of our *** circumventing the need for expensive and bulky FPA and wavelength selection components,our solution shows promise in advancing affordable and accessible NIR hyperspectral imaging technologies,thereby expanding the range of potential applications.

关键词： spectral Quantum mirror