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Classification of aviation incident causes using LGBM with improved cross-validation

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Journal of Systems Engineering and Electronics 2024年第2期35卷 396-405页

作者： ni Xiaomei WANG Huawei chen Lingzi LIN Ruiguan School of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Aeronautical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210023China

Aviation accidents are currently one of the leading causes of significant injuries and deaths worldwide. This entices researchers to investigate aircraft safety using data analysis approaches based on an advanced machine learning *** assess aviation safety and identify the causes of incidents, a classification model with light gradient boosting machine (LGBM)based on the aviation safety reporting system (ASRS) has been developed. It is improved by k-fold cross-validation with hybrid sampling model (HSCV), which may boost classification performance and maintain data balance. The results show that employing the LGBM-HSCV model can significantly improve accuracy while alleviating data imbalance. Vertical comparison with other cross-validation (CV) methods and lateral comparison with different fold times comprise the comparative approach. Aside from the comparison, two further CV approaches based on the improved method in this study are discussed:one with a different sampling and folding order, and the other with more CV. According to the assessment indices with different methods, the LGBMHSCV model proposed here is effective at detecting incident causes. The improved model for imbalanced data categorization proposed may serve as a point of reference for similar data processing, and the model’s accurate identification of civil aviation incident causes can assist to improve civil aviation safety.

关键词： aviation safety imbalance data light gradient boosting machine(LGBM) cross-validation(CV)

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Development of the electric automatic steering system for agricultural vehicles

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 209-214页

作者： Guangshun An Chong Yu juan Du Xiang Yin Youliang ni chengqian Jin School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina Nanjing Research Institute for Agricultural Mechanization of Ministry of Agriculture and Rural Affairs Nanjing 210014China

Automatic guidance of agricultural vehicles requires automatic execution of operation commands received from the navigation controller by using electronically controlled mechanisms for wheel steering,speed changing and work *** steering contributes as a prerequisite technique in automatic and semi-automatic agricultural *** research aimed to develop an electric automatic steering system that was compact in its structure and integrated into original steering mechanism in a simply and convenient way for aftermarket modification.A brushless motor and reducer assembly was utilized to provide an adequate steering torque instead of manual maneuver.A rapid assembling approach was proposed by passing the steering shaft through the hollow output shaft.A digital proportional-integral-differential(PID)algorithm was implemented to calculate the rotation speeds and directions by comparing the desired angle and the actual angle,which was implemented in a printed circuit board with a microcontroller unit(MCU)and interface *** unmanned wheeled tractor was applied as test platform to integrate the newly developed electric automatic steering *** were conducted to evaluate its performance in terms of stability and *** autonomous navigation system guided the tractor along target paths in the field by sending steering commands to the electric automatic steering *** results show that the steering angle error was less than 0.81°when desired steering angle was less than 10°.The lateral error difference was no more than 4.76 cm when repeating following the same target path,which indicated that the electric automatic steering system responded accurately and robustly to steering commands.

关键词： automatic steering automatic navigation agricultural vehicles

Intensive care unit-acquired weakness: Recent insights

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Journal of Intensive Medicine 2024年第1期4卷 73-80页

作者： juan chen Man Huang Department of General Intensive Care Unit The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009ZhejiangChina

Intensive care unit-acquired weakness(ICU-AW)is a common complication in critically ill patients and is associated with a variety of adverse *** include the need for prolonged mechanical ventilation and ICU stay;higher ICU,in-hospital,and 1-year mortality;and increased in-hospital ***-AW is associated with multiple risk factors including age,underlying disease,severity of illness,organ failure,sepsis,immobilization,receipt of mechanical ventilation,and other factors related to critical *** pathological mechanism of ICUAW remains unclear and may be considerably *** review aimed to evaluate recent insights into ICU-AW from several aspects including risk factors,pathophysiology,diagnosis,and treatment strategies;this provides new perspectives for future research.

关键词： Intensive care unit-acquired weakness Muscle weakness Muscle atrophy Risk factor Mechanism Treatment

Production of Functional Materials Derived from Regenerated Silk Fibroin by Utilizing 3D Printing and Biomimetic Enzyme-induced Mineralization

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Chinese Journal of Polymer Science 2024年第3期42卷 299-310,I0005页

作者： ni chen Fei-Yu Luo Gong-Wen Yang Jin-Rong Yao Xin chen Zheng-Zhong Shao State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced Materials and Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique,integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase(ALP), was developed. Initially,a pre-cured hydrogel of regenerated silk fibroin(RSF) with a small quantity of hydroxypropyl cellulose(HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate(Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization ***, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures.

关键词： Silk protein Alkaline phosphatase Extrusion-based printing Biomineralization

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A modified back analysis method for deep excavation with multi-objective optimization procedure

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1373-1387页

作者： chenyang Zhao Le chen Pengpeng ni Wenjun Xia Bin Wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Guangdong Research Center for Underground Space Exploitation Technology School of Civil EngineeringSun Yat-sen UniversityGuangzhou510275China Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) Zhuhai519000China Jiangsu Provincial Transportation Engineering Construction Bureau Nanjing210004China

Real-time prediction of excavation-induced displacement of retaining pile during the deep excavation process is crucial for construction *** paper proposes a modified back analysis method with multi-objective optimization procedure,which enables a real-time prediction of horizontal displacement of retaining pile during *** opposed to the traditional stage-by-stage back analysis,time series monitoring data till the current excavation stage are utilized to form a multi-objective ***,the multi-objective particle swarm optimization (MOPSO) algorithm is applied for parameter *** optimized model parameters are immediately adopted to predict the excavation-induced pile deformation in the continuous construction *** achieve efficient parameter optimization and real-time prediction of system behavior,the back propagation neural network (BPNN) is established to substitute the finite element model,which is further implemented together with MOPSO for automatic *** proposed approach is applied in the Taihu tunnel excavation project,where the effectiveness of the method is demonstrated via the comparisons with the site monitoring *** method is reliable with a prediction accuracy of more than 90%.Moreover,different optimization algorithms,including non-dominated sorting genetic algorithm (NSGA-II),Pareto Envelope-based Selection Algorithm II (PESA-II) and MOPSO,are compared,and their influences on the prediction accuracy at different excavation stages are *** results show that MOPSO has the best performance for high dimensional optimization task.

关键词： Multi-objective optimization Back analysis Surrogate model Multi-objective particle swarm optimization(MOPSO) Deep excavation

Sodium butyrate alleviates fructose-induced non-alcoholic fatty liver disease by remodeling gut microbiota to promoteγ-amino butyric acid production

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Food Science and Human Wellness 2024年第2期13卷 961-971页

作者： Qu chen Lei Wu Aijia Zhang chen Wu Liuping Cai Yingping Xiao Yingdong ni Key Laboratory of Animal Physiology and Biochemistry Ministry of Agriculture and Rural AffairsNanjing Agricultural UniversityNanjing 210095China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Agro-product Safety and NutritionZhejiang Academy of Agricultural SciencesHangzhou 310022China

Sodium butyrate(NaB)can regulate lipid metabolism and inhibit hepatic *** study aimed to investigate whether NaB can alleviate fructose-induced hepat ic steatosis via remodeling the gut microbiota and evaluate the anti-fatty liver *** results showed that NaB and NaB-remodeled gut microbiota significantly alleviated fructose-induced hepatic steatosis and increased plasma uric acid and fructose ***,both NaB and NaB-remodeled gut microbiota increased the abundance of Lactobacillus and altered the levels of plasma amino acids(upregulating gamma-amino butyric acid(GABA)and downregulating L-glutamic acid and L-arginine)in fructose-exposed *** correlation analysis showed that GABA levels positively correlated with Lactobacillus abundance,and increased GABA levels might promote the reduction of the hepatic triglyceride *** studies confirmed that GABA significantly reduced lipid deposition in mouse hepatocytes induced via fructose pretreatment in *** findings suggested that NaB could ameliorate fructose-induced hepatic steatosis by regulating gut microbiota.

关键词： Butyrate Fructose Gut microbiota Hepatic steatosis

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Effects of Aphidius gifuensis on the feeding behavior and potato virus Y transmission ability of Myzus persicae

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Insect Science 2018年第6期25卷 1025-1034页

作者： Ying-Qin He Yong-Qiang Zhang juan-ni chen Wen-Long chen Xian-Yi Zeng Hai-Tao chen Wei Ding College of Plant Protection Southwest UniversityChongqingChina Guizhou Key Laboratory of Plant Disease and Pest Management for Mountain Agriculture Institute of EntomologyGuizhou UniversityGuiyangChina Chongqing Institute of Tobacco Science ChongqingChina

The stylet penetration behavior of aphids when feeding on plants is associated with virus acquisition and *** gifuensis (Ashmead)is a primary endoparasitoid of Myzuspersicae (Sulzer)which is the most efficient vector of plant viruses. Information about the effects ofparasitoid on aphid and virus transmission can provide an essential foundation for designing effective biological control *** study aimed to investigate the effects *** on the feeding behavior and potato virus Y (PVY) transmission ability of *** results showed that after *** was para-sitized by ***,the duration of the first probe significantly ***, *** exerted remarkable effects on aphid feeding in phloem *** contribution of the E1 waveform to the phloem phase was significantly higher in all parasitized aphids than in the control *** the time of infestation increased for parasitized aphids,the total duration of phloem sap ingestion ***,the percentage of time *** spent in the xylem and phloem phases only changed significantly on day *** percent transmission of PVY by the aphids parasitized on day 5 was lower than that in the control,but no significant differences were *** significance of this work is the demonstration that *** can impede the feeding behavior of ***,which sheds light on the biological basis *** as a natural enemy, but unfortunately does not provide an immediate solution for disrupting the transmission of PVY.

关键词： Braconidae electrical penetration graphs feedingbehavior Myzuspersicae parasitoids virus transmission

niR-IIb-triggered photodynamic therapy combined with chemotherapy platform based on rare-earth-doped nanoparticles

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Rare Metals 2024年第7期43卷 3220-3231页

作者： Zhuo Tu Yong Wan juan Ge chen-chen Li Tao Liang Zhen Li College of Health Science and Engineering College of Chemistry and Chemical EngineeringHubei University

Photodynamic therapy（PDT）,with high spatiotemporal selectivity,minimal side effects and less drug resistance,has emerged as a promising approach for the treatment of ***,inadequate penetration depth and poor efficacy seriously restrict its practical *** address these challenges,we developed a combined therapy platform（RENP@C/D-FA） based on rare-earth-doped nanoparticles（RENPs） with a structure of NaErF4:Tm（0.5%）@NaYF4,on which photosensitizer Ce6（chlorin e6） and chemo-therapeutic drug（DOX）(doxorubicin) were loaded by encapsulating with an amphiphilic polymer distearoyl phosphatidylethanolamine-polyethylene glycol-folic acid（DSPE-PEG-FA）.RENPs with NaErF4as the matrix possess multiple excitation/emission peaks,enabling activation of PDT under near-infrared-Ⅱb（niR-Ⅱb,1500-1700 nm） excitation and luminescence imaging in niR-Ⅱb region by absorbing 808 nm near-infrared ***,DOX can be selectively released in the acidic microenvironment of *** from the tumor targeting capability of folic acid,this platform can successfully ablate tumor cells and inhibit tumor growth by combining PDT and *** innovative approach holds great promise as a powerful tool for cancer treatment,showing the potential to revolutionize PDT.

关键词： Photodynamic therapy Rare-earth-doped nanoparticles niR-IIb Chemotherapy Combined therapy

Body-force modeling considering induced upstream effects for a transonic compressor with total temperature distortion

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Chinese Journal of Aeronautics 2024年第6期37卷 7-19页

作者： Jiahui QIU chen YANG Wenqiang ZHANG Min ZHANG juan DU Digital Twin Research Center Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Engineering and Science University of Chinese Academy of SciencesBeijing 100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Chinese Academy of SciencesBeijing 100190China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

To numerically study the impact of total temperature distortion on a transonic compressor with reduced computational costs,a Body-Force Model(BFM)is ***,the interactions between the distorted flow and the compressor are analyzed using full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS)results and the orbit *** is found that the induced swirl distortion and the mass flux nonuniformity are intensified in the compressor upstream flow field.A correction factor is thus added to the BFM to account for the effect of the induced swirl,which is crucial for the accurate representation of distortion transfer in the ***,steady simulations with large-amplitude 180circumferential total temperature distortion are performed using the developed *** is shown that the distorted compressor map simulated with the BFM matches well with URANS *** circumferential phase shift of total temperature and the generation of the additional total pressure distortion across the rotor are in line with the time-averaged URANS flow *** compressor upstream effects on the distorted inflow can also be exactly *** above-mentioned results demonstrate the BFM developed in this paper can effectively capture the distorted flow features inside the compressor,and significantly reduce the computational costs by five orders of magnitude compared with URANS.

关键词： Upstream effect Orbit method Induced swirl distortion Body force model Correction factor Time-averaged URANS