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A Credit Card Fraud Model Prediction Method Based on Penalty Factor Optimization AWTadaboost

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Computers, Materials & Continua 2023年第3期74卷 5951-5965页

作者： Wang Ning Siliang Chen Fu Qiang Haitao Tang Shen Jie college of Computer and Communication Hunan Institute of EngineeringXiangtan411104China college of Computational Science and Electronics Hunan Institute of EngineeringXiangtan411104China

With the popularity of online payment, how to perform creditcard fraud detection more accurately has also become a hot issue. And withthe emergence of the adaptive boosting algorithm (Adaboost), credit cardfraud detection has started to use this method in large numbers, but thetraditional Adaboost is prone to overfitting in the presence of noisy ***, in order to alleviate this phenomenon, this paper proposes a newidea: using the number of consecutive sample misclassifications to determinethe noisy samples, while constructing a penalty factor to reconstruct thesample weight assignment. Firstly, the theoretical analysis shows that thetraditional Adaboost method is overfitting in a noisy training set, which leadsto the degradation of classification accuracy. To this end, the penalty factorconstructed by the number of consecutive misclassifications of samples isused to reconstruct the sample weight assignment to prevent the classifierfrom over-focusing on noisy samples, and its reasonableness is ***, by comparing the penalty strength of the three different penalty factorsproposed in this paper, a more reasonable penalty factor is ***, in order to make the constructed model more in line with theactual requirements on training time consumption, the Adaboost algorithmwith adaptive weight trimming (AWTAdaboost) is used in this paper, so thepenalty factor-based AWTAdaboost (PF_AWTAdaboost) is finally ***, PF_AWTAdaboost is experimentally validated against other traditionalmachine learning algorithms on credit card fraud datasets and otherdatasets. The results show that the PF_AWTAdaboost method has betterperformance, including detection accuracy, model recall and robustness, thanother methods on the credit card fraud dataset. And the PF_AWTAdaboostmethod also shows excellent generalization performance on other *** the experimental results, it is shown that the PF_AWTAdaboost algorithmhas better classification

关键词： Credit card fraud noisy samples penalty factors AWTadaboost algorithm

Design of an Acoustic Levitator for Three-Dimensional Manipulation of Numerous Particles

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Chinese Physics Letters 2019年第9期36卷 28-31页

作者： Di Wu De-Yao Yin Zhi-Yuan Xiao Qing-Fan Shi Experimental Center of Physics Beijing Institute of TechnologyBeijing 100081

We present a design of an acoustic levitator consisting of three pairs of opposite transducer *** orthogonal standing waves create a large number of acoustic traps at which the particles are levitated in *** changing the phase difference of transducer arrays,three-dimensional manipulation of particles is successfully ***,the relationship between the translation of particles and the phase difference is experimentally investigated,and the result is in agreement with the theoretical *** design can expand the application of acoustic levitation in many fields,such as biomedicine,ultrasonic motor and new materials processing.

关键词： Design of an Acoustic Levitator for Three-Dimensional Manipulation of Numerous Particles

Collision tumor of primary malignant lymphoma and adenocarcinoma in the colon diagnosed by molecular pathology:A case report and literature review

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World Journal of Clinical Cases 2023年第26期11卷 6289-6297页

作者： Meng Jiang Xiao-Ping Yuan School of Medicine Sun Yat-sen UniversityShenzhen 518107Guangdong ProvinceChina Department of Radiology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120Guangdong ProvinceChina

BACKGROUND Collision tumors of primary malignant lymphoma and adenocarcinoma in the colon are *** diffuse large B-cell lymphoma(DLBCL)–adenocarcinoma collision tumors are especially *** SUMMARY A 74-year-old woman presented with abdominal pain of 1 mo *** under colonoscopy revealed adenocarcinoma of the ascending ***,the patient underwent laparoscopic radical resection of right colon cancer with lymph node dissection.A collision tumor was found incidentally through postoperative pathological *** analysis showed a collision tumor of DLBCL with germinal center B-cell subtype and TP53 mutation,and adenocarcinoma arising in a tubulovillous adenoma in the colon,with BRAF mutation and mutL homolog 1 promoter *** patient died 3 mo after *** our knowledge,this is the 23rd reported case of collision tumor of colorectal adenocarcinoma and *** mean age of the 23 patients was 73 *** most common site was the *** were 15 cases with followup data including 11 living and four dead with a 3-year overall survival rate of 71.5%.CONCLUSION Based on pathological and genetic analysis,surgery combined with chemotherapy or chemoradiotherapy may have good therapeutic effects for collision tumor.

关键词： Collision tumor Colorectal adenocarcinoma Primary colonic lymphoma Molecular pathological analysis Case report

The Competitive Adsorption Characteristics of Welan Gum and Superplasticizer in Cement Mortar

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Journal of Wuhan University of Technology(Materials Science) 2016年第1期31卷 131-138页

作者：赵青林 ZHANG Yulin LIU Ciqi ZENG Luping CHEN Shihua State Key Laboratory of Silicate Materials for Architecture Wuhan University of Technology Wuhan 430070 China School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

Welan gum has been widely used in oil cement and grouting materials for its excellent rheological properties and anti-bleeding,and most of all,being friendly to the ***,when welan gum was added,the fluidity of mortar decreased sharply,so it should be used together with a superplasticizer to enable good *** its powerful charge density in the molecular structure,the competitive adsorption between welan gum and other admixtures happened remarkably during the addition ***,we experimentally studied on the bleeding rate and rheological properties of cement slurry,fluidity and mechanical properties of mortar with welan gum mixed with superplasticizer,aiming at understanding the competitive adsorption phenomenon by application of welan gum mixed with *** measuring the hydration heat and zeta potential,the mechanism of interaction of welan gum with superplasticizer was deduced and *** results showed that it could ensure a good dispersion effect when welan gum is mixed with the two kinds of *** gum had little impact on the naphthalene superplasticizer,but did have a substantial influence on *** practice,adding welan gum after PCE acted with cement for 2 min could effectively avoid the competitive adsorption and then achieve better *** this viewpoint for mortar with PCE,new delay release welan gum needs further research and development.

关键词： welan gum superplasticizer competitive adsorption properties

Leaching behavior of zinc and copper from zinc refinery residue and filtration performance of pulp under the hydrothermal process

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 21-32页

作者： Lei Cao Ya-long Liao Gong-chu Shi Yu Zhang Mu-yuan Guo Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology

This study aims to investigate the leaching behavior and filtration performance of zinc refinery residue under hydrothermal conditions. The relationships between the structure and morphology of silicon in the leaching residue and the pulp filtration performance were explored by determining the pulp filtration speed, analyzing quantitatively the silicon content in the leachate, and characterizing the leaching residue structure. The results show that hydrothermal leaching induces the coagulation–hydrolysis of the silicon in solution, consequently altering the microstructure of the leaching residue, and that silicon oxygen tetrahedra([SiO_4]^(4-)) form the main skeleton structure of the residue. The results obtained also show that the leaching rates of zinc and copper are 98.1% and 98.7%, respectively, and that the filtration speed is 526.32 L/(m^2·h) under the conditions of sulfuric acid concentration of 140 g/L, leaching temperature of 160°C, leaching time of 3.0 h, oxygen partial pressure of 0.75 MPa, stirring speed of 600 r/min, and a liquid-to-solid ratio of 10 mL/g.

关键词： zinc refinery residue hydrothermal leaching filtration performance mesoporous structure

Developmental impacts and toxicological hallmarks of silver nanoparticles across diverse biological models

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Environmental Science and Ecotechnology 2024年第3期19卷 60-79页

作者： Yán Wāng Yapeng Han De-Xiang Xu Department of Toxicology School of Public Health&Key Laboratory of Environmental Toxicology of Anhui Higher Education InstitutesAnhui Medical UniversityHefei230032China

Silver nanoparticles(AgNPs),revered for their antimicrobial prowess,have become ubiquitous in a range of products,from biomedical equipment to food ***,amidst their rising popularity,concerns loom over their possible detrimental effects on fetal development and subsequent adult *** review delves into the developmental toxicity of AgNPs across diverse models,from aquatic species like zebrafish and catfish to mammalian rodents and in vitro embryonic stem *** focus encompasses the fate of AgNPs in different contexts,elucidating associated hazardous results such as embryotoxicity and adverse pregnancy ***,we scrutinize the enduring adverse impacts on offspring,spanning impaired neurobehavior function,reproductive disorders,cardiopulmonary lesions,and *** hallmarks of developmental harm are identified,encompassing redox imbalances,inflammatory cascades,DNA damage,and mitochondrial ***,we explore potential explanations,linking immunoregulatory dysfunction and disrupted epigenetic modifications to AgNPsinduced developmental *** substantial progress,our understanding of the developmental risks posed by AgNPs remains incomplete,underscoring the urgency of further research in this critical area.

关键词： Silver nanoparticles(AgNPs) Developmental toxicity Maternal exposure Fetal development Redox imbalance Mitochondrial dysfunction

Mechanical Properties of Interlocked-ring Polymers: A Molecular Dynamics Simulation Study

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Chinese Journal of Polymer Science 2019年第12期37卷 1298-1304,I0008页

作者： Zheng-Tao Wu Jia-Jia Zhou college of Engineering Zhejiang Normal UniversityJinhua 321004China School of Chemistry Beihang UniversityBeijing 100191China

Interlocked-ring polymers,also known as polycatenanes,possess an interesting molecular *** polymers are composed of many interlocked rings in a linear *** topological constrain between neighboring rings distinguishes the interlockedring polymer from its linear *** we present extensive molecular dynamic simulations on the interlocked-ring polymers and analyze the static properties of the *** applying external forces to the polymer,we also study the force-extension curves of the polymer,which provides rich information about the mechanical properties of the interlockedring polymers.

关键词： Poly catenanes Molecular dynamics simulation Force-extension Entanglement

Developing the QSPR model for predicting the storage lipid/water distribution coefficient of organic compounds

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Frontiers of Environmental Science & Engineering 2021年第2期15卷 87-94页

作者： Miao Li Jian Li Yuchen Lu Cenyang Han Xiaoxuan Wei Guangcai Ma Haiying Yu college of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China

The distribution of organic compounds in stored lipids affects their migration,transformation,bioaccumulation,and toxicity in *** storage lipid/water distribution coefficient(log K_(lip/w))of organic chemicals,which quantitatively determines such distribution,has become a key parameter to assist their ecological security and health *** to the impossibility to measure K_(lip/w)values for a huge amount of chemicals,it is necessary to develop predictive *** this work,a quantitative structure-property relationship(QSPR)model for estimating log K_(lip/w)values of small organic compounds was constructed based on 305 experimental log K_(lip/w)*** chemical descriptors and n-octanol/water partitioning coefficient were employed to characterize the intermolecular interactions that dominate log K_(lip/w)*** hydrophobic and electrostatic interactions and molecular size have been found to play important roles in governing the distribution of chemicals between lipids and aqueous *** regression(R2=0.959)and validation(Q2=0.960)results indicate good fitting performance and robustness of the developed model.A comparison with the predictive performance of other commercial software further proves the higher accuracy and stronger predictive ability of the developed K_(lip/w)predictive ***,it can be used to predict the K_(lip/w)values of cycloalkanes,long-chain alkanes,halides(with fluorine,chlorine,and bromine as substituents),esters(without phosphate groups),alcohols(without methoxy groups),and aromatic compounds.

关键词： Storage lipid/water distribution coefficient log Klip/w Organic compounds QSPR Quantum chemical descriptors

Synthesis and Coloring Mechanism of Metallic Glaze in R_(2)O-RO-Al_(2)O_(3)-SiO_(2)-P_(2)O_(5)System

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Journal of Wuhan University of Technology(Materials Science) 2024年第6期39卷 1416-1424页

作者： CHEN Yanlin FU Qiong YANG Yuhang WEI Feng LIU Dongyang WANG Juan Hubei Provincial Key Laboratory of Green Materials for Light Industry Hubei University of TechnologyWuhan 430068China New Materials and Green Manufacturing Talent Introduction and innovation Demonstration Base Hubei University of TechnologyWuhan 430068China

A copper-red and silver-white metallic glaze of R_(2)O-RO-Al_(2)O_(3)-SiO_(2)-P_(2)O_(5)system was synthesized by adjusting the firing temperature and glaze *** coloration mechanism of the metallic glaze was revealed via investigation of the microstructure of the *** research reveals that the metallic glaze with different colors is mainly due to the amount of Fe_(2)O_(3).The metallic glaze shows a silver-white luster due to a structural color ofα-Fe_(2)O_(3)crystals with a good orientation when the sample contains 0.0939 mol of Fe_(2)O_(3),maintaining temperatures at 1150℃for 0.5 *** metallic glaze is copper-red which is dominated by the coupling of chemical and structural color ofα-Fe_(2)O_(3)crystals when the sample contains 0.0783 mol of Fe_(2)O_(3).After testing the amount of SiO_(2),we find that 4.0499 mol is the optimal amount to form the ceramic network,and 0.27 mol AlPO_(4)is the best amount to promote phase separation.

关键词： metallic glaze phase separation coloring mechanism chemical color structural color