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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 algorithm.To 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)

Reliability of a Multicomponent Stress-strength Model Based on a Bivariate Kumaraswamy Distribution with Censored Data

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua CHENG school of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored scheme.These elements(X1,Y1),(X2,Y2),…,(Xk,yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy distribution.The system is regarded as operating only if at least s out of k(1≤s≤k)strength variables exceed the random stress.The multicomponent reliability of the system is given by Rs,k=P(at least s of the(Z1,…,Zk)exceed T)where Zi=min(Xi,Yi),i=1,…,k.The Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit forms.The uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is known.The asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,k.The reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation

Significantly improved near-field communication antennas based on novel Ho^(3+)and Co^(2+)ions co-doped Ni-Zn ferrites

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Journal of Advanced Ceramics 2024年第3期13卷 293-309页

作者： pao Yang Zhiqing Liu Hongbin Qi Xiuli Fu Zhijian Peng school of Science China University of GeosciencesBeijing 100083China school of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Kunshan GuoLi Electronic Technology Co. Ltd.Kunshan 215300China

In near-field communication(NFC)antennas,soft magnetic ferrites are usually applied as a substrate to reduce eddy current loss and increase magnetic field coupling.For this purpose,the applied ferrites are required to have high permeability and saturation magnetization together with low magnetic loss and dielectric loss.However,for most soft magnetic ferrites,it is difficult to meet all the requirements.Herein novel Ni-Zn ferrite ceramics co-doped by Ho^(3+)and Co^(2+)ions with chemical formula Ni_(0.5-x)Zn_(0.5)Ho_(0.02)Co_(x)Fe_(1.98)O_(4)(x=0-0.2)were designed and prepared to balance these needs on the basis of molten salt synthesis with metal nitrates as raw materials and potassium hydroxide(KOH)as the precipitation agent and molten salt precursor.After the substitution of Ho^(3+),the saturation magnetization and initial permeability decrease,but with further doping of Co^(2+),the saturation magnetization gradually increases,while the initial permeability continues to decrease.When x=0.1,the sample will have the lowest dielectric constant,magnetic and dielectric loss,as well as the highest Curie temperature(305℃).Moreover,the acquired Ni-Zn ferrites have been applied simulatively in NFC antennas,revealing that the device manufactured with the optimal Ni_(0.4)Zn_(0.5)Ho_(0.02)Co_(0.1)Fe_(1.98)O_(4)ferrite ceramics would have significantly improved performance at 13.56 MHz with low leakage and long transmit distance of magnetic field.Therefore,the Ni_(0.4)Zn_(0.5)Ho_(0.02)Co_(0.1)Fe_(1.98)O_(4)ferrite ceramics would be a good candidate for NFC antenna substrates.

关键词： electromagnetic properties co-doping microstrip antennas Ni-Zn ferrite

Prediction of Lubricant Physicochemical Properties Based on Gaussian Copula Data Expansion

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 161-174页

作者： Feng Xin Yang Rui Xie Peiyuan Xia Yanqiu school of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,pao40,and PriEco3000 component in a composite base oil system on the performance of lubricants.The study was conducted under small laboratory sample conditions,and a data expansion method using the Gaussian Copula function was proposed to improve the prediction ability of the hybrid model.The study also compared four optimization algorithms,sticky mushroom algorithm(SMA),genetic algorithm(GA),whale optimization algorithm(WOA),and seagull optimization algorithm(SOA),to predict the kinematic viscosity at 40℃,kinematic viscosity at 100℃,viscosity index,and oxidation induction time performance of the lubricant.The results showed that the Gaussian Copula function data expansion method improved the prediction ability of the hybrid model in the case of small samples.The SOA-GBDT hybrid model had the fastest convergence speed for the samples and the best prediction effect,with determination coefficients(R^(2))for the four indicators of lubricants reaching 0.98,0.99,0.96 and 0.96,respectively.Thus,this model can significantly reduce the model’s prediction error and has good prediction ability.

关键词： base oil data augmentation machine learning performance prediction seagull algorithm

Socio-economic vulnerability level in the Jeneberang watershed in Gowa Regency,South Sulawesi Province,Indonesia

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Regional Sustainability 2024年第1期5卷 69-79页

作者： Andi Rachmat ARFADLY Hazairin ZUBAIR MAHYUDDIN Andang Suryana SOMA Graduate school Hasanuddin UniversityMakassar90245Indonesia Faculty of Agriculture Hasanuddin UniversityMakassar90245Indonesia

Jeneberang watershed is vital,particularly for people living in Gowa Regency(South Sulawesi Province,Indonesia),who benefit from its many advantages.Landslides and floods occur every year in the Jeneberang watershed,so it is imperative to understand the socio-economic vulnerability of this region.This research aims to identify the vulnerability level of the Jeneberang watershed so that the government can prioritize areas with high vulnerability level and formulate effective strategies to reduce these the vulnerability.Specifically,this study was conducted in 12 districts located in the Jeneberang watershed.The primary data were collected from questionnaires completed by community members,community leaders,and various stakeholders,and the secondary data were from the Landsat satellite imagery in 2020,the Badan Push Statistic of Gowa Regency,and some governmental agencies.The socio-economic vulnerability variables were determined using the Multiple Criteria Decision Analysis(MCDA)method,and each variable was weighted and analyzed using the Geographical Information System(GIS).The study reveals that the levels of socio-economic vulnerability are affected by variables such as population density,vulnerable groups(disabled people,elderly people,and young people),road network and settlement,percentage of poor people,and productive land area in the Jeneberang watershed.Moreover,all of the 12 districts in the Jeneberang watershed are included in the medium vulnerability level,with the mean percentage of socio-economic vulnerability around 50.92%.The socio-economic vulnerability of Bajeng,Pallangga,and Somba Opu districts is categorized at high level,the socio-economic vulnerability of Bungaya,Parangloe,and Tombolo pao districts is classified as medium level,and the remaining 6 districts(Barombong,Bontolempangan,Bontomarannu,Manuju,Parigi,and Tinggimoncong)are ranked as low socio-economic vulnerability.This study can help policy-makers to formulate strategy that contributes to the protection of biodiversity and sustainable

关键词： Socio vulnerability Economic vulnerability Population density Vulnerable groups Road network and settlement Productive land area Jeneberang watershed

A Research on Senior People Online Consumption in China-From Perspective of Providing Technology Support

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社会学研究:英文版 2023年第5期13卷 255-259页

作者： Hui Lu Zikuan Bai Ruoyi Rebecca Tu Ruoni Elizabeth Tu Yanfei Zeng Xiangyu Chen Sheng Zhang Iolani school HawaiiUSA yk pao school ShanghaiChina Shanghai American school ShanghaiChina Gaston Day school Shanghai Shangde ShanghaiChina Shanghai Academy of Social Sciences ShanghaiChina

While the internet skills of the elderly is no longer a big problem,it is still necessary to further improve the online shopping experience and activity of the elderly.Evidently,the frequency of seniors shopping online is not nearly as high as the younger generation,as the elderly online shopping frequency is still calculated by weeks.People with higher education and younger age are more likely to accept technology products and understand how to use them,but people with lower education and older age will find it harder to use technology product.The majority of the elderly have a vision for the further development of technology to help them.This study shows that the elderly group shopping demand is large,but when the majority of the elderly choose offline consumption,the option of just a simple online solution is insufficient.Some shopping apps have made improvements in such aspects as font enlargement,color contrast enhancement and simplified operation steps.However,these improvements only solved the superficial problems,and failed to consider and solve the problems based on the experience of the elderly.

关键词： aging society online consumption shopping technology products

Systemic treatment for inoperable pancreatic adenocarcinoma: review and update

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Chinese Journal of Cancer 2014年第6期33卷 267-276页

作者： Stephen L.Chan Sin T.Chan Eric H.Chan Zhe-Xi He State Key Laboratory in Oncology in South China Sir YK Pao Center for Cancer Department of Clinical Oncology and Hong Kong Cancer Institute and Prince of Wales Hospital The Chinese University of Hong Kong The Faculty of Medicine The Chinese University of Hong Kong

There have been many clinical trials conducted to evaluate novel systemic regimens for unresectable pancreatic cancer. However, most of the trial results were negative, and gemcitabine monotherapy has remained the standard systemic treatment for years. A number of molecular targeted agents, including those against epidermal growth factor receptor and vascular endothelial growth factor receptors, have also been tested. In recent years, there have been some breakthroughs in the deadlock: three regimens, namely gemcitabine-erlotinib, FOLFIRINOX, and gemcitabine-nab-paclitaxel, have been shown to prolong the overall survival of patients when compared with gemcitabine monotherapy. In addition, emerging data suggested that the membrane protein human equilibrative nucleotide transporter 1 is a potential biomarker with which to predict the efficacy of gemcitabine. Here we review the literature on the development of systemic agents for pancreatic cancer, discuss the current choices of treatment, and provide future directions on the development of novel agents.

关键词：全身治疗胰腺癌审查血管内皮生长因子受体表皮生长因子受体手术临床试验靶向药物

Targeting epigenetic and posttranslational modifications regulating ferroptosis for the treatment of diseases

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Signal Transduction and Targeted Therapy 2024年第1期9卷 105-149页

作者： Yumin Wang Jing Hu Shuang Wu Joshua S.Fleishman Yulin Li Yinshi Xu Wailong Zou Jinhua Wang Yukuan Feng Jichao Chen Hongquan Wang Department of Respiratory and Critical Care Medicine Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049PR China Department of Pathogen Biology School of Basic Medical SciencesTianjin Medical UniversityTianjin 300060PR China Department of Neurology Zhongnan Hospital of Wuhan UniversityWuhan 430000PR China Department of Pharmaceutical Sciences College of Pharmacy and Health SciencesSt.John’s UniversityQueensNY 11439USA Department of Outpatient Aerospace Center HospitalPeking University Aerospace School of Clinical MedicineBeijing 100049PR China Beijing Key Laboratory of Drug Target and Screening Research Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050PR China Department of Pancreatic Cancer Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060PR China

Ferroptosis,a unique modality of cell death with mechanistic and morphological differences from other cell death modes,plays a pivotal role in regulating tumorigenesis and offers a new opportunity for modulating anticancer drug resistance.Aberrant epigenetic modifications and posttranslational modifications(PTMs)promote anticancer drug resistance,cancer progression,and metastasis.Accumulating studies indicate that epigenetic modifications can transcriptionally and translationally determine cancer cell vulnerability to ferroptosis and that ferroptosis functions as a driver in nervous system diseases(NSDs),cardiovascular diseases(CVDs),liver diseases,lung diseases,and kidney diseases.In this review,we first summarize the core molecular mechanisms of ferroptosis.Then,the roles of epigenetic processes,including histone PTMs,DNA methylation,and noncoding RNA regulation and PTMs,such as phosphorylation,ubiquitination,SUMOylation,acetylation,methylation,and ADP-ribosylation,are concisely discussed.The roles of epigenetic modifications and PTMs in ferroptosis regulation in the genesis of diseases,including cancers,NSD,CVDs,liver diseases,lung diseases,and kidney diseases,as well as the application of epigenetic and PTM modulators in the therapy of these diseases,are then discussed in detail.Elucidating the mechanisms of ferroptosis regulation mediated by epigenetic modifications and PTMs in cancer and other diseases will facilitate the development of promising combination therapeutic regimens containing epigenetic or PTM-targeting agents and ferroptosis inducers that can be used to overcome chemotherapeutic resistance in cancer and could be used to prevent other diseases.In addition,these mechanisms highlight potential therapeutic approaches to overcome chemoresistance in cancer or halt the genesis of other diseases.

关键词： diseases epigenetic overcome

In-situ formation of nitrogen doped microporous carbon nanospheres derived from polystyrene as lubricant additives for anti-wear and friction reduction

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Friction 2024年第3期12卷 439-451页

作者： Yixin WANG Qi LU Huijie XIE Shujuan LIU Qian YE Feng ZHOU Weimin LIU State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

This study presents a nitrogen-doped microporous carbon nanospheres(N@MCNs)prepared by a facile polymerization–carbonization process using low-cost styrene.The N element in situ introduces polystyrene(PS)nanospheres via emulsion polymerization of styrene with cyanuric chloride as crosslinking agent,and then carbonization obtains N@MCNs.The as-prepared carbon nanospheres possess the complete spherical structure and adjustable nitrogen amount by controlling the relative proportion of tetrachloromethane and cyanuric chloride.The friction performance of N@MCNs as lubricating oil additives was surveyed utilizing the friction experiment of ball-disc structure.The results showed that N@MCNs exhibit superb reduction performance of friction and wear.When the addition of N@MCNs was 0.06 wt%,the friction coefficient of pao-10 decreased from 0.188 to 0.105,and the wear volume reduced by 94.4%.The width and depth of wear marks of N@MCNs decreased by 49.2% and 94.5%,respectively.The carrying capacity of load was rocketed from 100 to 400 N concurrently.Through the analysis of the lubrication mechanism,the result manifested that the prepared N@MCNs enter clearance of the friction pair,transform the sliding friction into the mixed friction of sliding and rolling,and repair the contact surface through the repair effect.Furthermore,the tribochemical reaction between nanoparticles and friction pairs forms a protective film containing nitride and metal oxides,which can avert direct contact with the matrix and improve the tribological properties.This experiment showed that nitrogen-doped polystyrene-based carbon nanospheres prepared by in-situ doping are the promising materials for wear resistance and reducing friction.This preparing method can be ulteriorly expanded to multi-element co-permeable materials.Nitrogen and boron co-doped carbon nanospheres(B,N@MCNs)were prepared by mixed carbonization of N-enriched PS and boric acid,and exhibited high load carrying capacity and good tribological properties.

关键词： lubricant additives hypercrosslinked polystyrene carbon nanospheres friction reduction anti-wear