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PAssAGE OF PArTICLEs THrOUGH MATTEr

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Chinese Physics C 2016年第10期40卷 441-455页

作者： H.Bichsel D.E.Groom s.r.klein University of Washington LBNL

revised August 2015 by H. Bichsel （University of Washington）, D.E Groom （LBNL）, and s.r. klein （LBNL）. This review covers the interactions of photons and electrically charged particles in matter, concentrating on energies of interest for high-energy physics and astrophysics and processes of interest for particle detectors （ionization, Cherenkov radiation, transition radiation）.

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Kinematic analysis of flexible bipedal robotic systems

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.M.sHAFEI s.r.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous researchers.What distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic systems.This is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases considerably.Moreover,the human leg bones that are involved in walking are supported by viscoelastic muscles and ligaments.Therefore,for achieving more exact results,it is essential to model the robot links with viscoelastic properties.To this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of motion.The most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational force.The extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned goal.To overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue problem.By solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are determined.The effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of robotic systems are also studied.The findings o

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Tribologically induced nanostructural evolution of carbon materials: A new perspective

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Friction 2024年第1期12卷 144-163页

作者： Guilherme Oliveira NEVEs Nicolás ArAYA Diego Berti sALVArO Thiago de souza LAMIM renan Oss GIACOMELLI Cristiano BINDEr Aloisio Nelmo klein JoséDaniel Biasoli de MELLO Laboratório de Materiais Universidade Federal de Santa CatarinaSanta Catarina 88040-900Brazil Departamento de Ingeniería Mecánica Facultad de IngenieríaUniversidad del Bío-BíoConcepcion 4070-386Chile Universidad de Concepción Concepcion 4070-386Chile sENAI Innovation Institute for Laser Processing Santa Catarina 89218-153Brazil Universidade Federal de Uberlândia Minas Gerais 38408-100Brazil

Carbon-based solid lubricants are excellent options to reduce friction and wear,especially with the carbon capability to adopt different allotropes forms.On the macroscale,these materials are sheared on the contact along with debris and contaminants to form tribolayers that govern the tribosystem performance.Using a recently developed advanced raman analysis on the tribolayers,it was possible to quantify the contactinduced defects in the crystalline structure of a wide range of allotropes of carbon-based solid lubricants,from graphite and carbide-derived carbon particles to multi-layer graphene and carbon nanotubes.In addition,these materials were tested under various dry sliding conditions,with different geometries,topographies,and solid-lubricant application strategies.regardless of the initial tribosystem conditions and allotrope level of atomic ordering,there is a remarkable trend of increasing the point and line defects density until a specific saturation limit in the same order of magnitude for all the materials tested.

关键词： carbon nanostructures tribology raman spectroscopy defects quantification tribolayer solid lubrication

An Efficient Modelling of Oversampling with Optimal Deep Learning Enabled Anomaly Detection in streaming Data

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China Communications 2024年第5期21卷 249-260页

作者： r.rajakumar s.sathiya Devi srinivasa ramanujan Centre SASTRA Deemed UniversityKumbakonamTamil Nadu 612001India University College of Engineering BIT CampusAnna UniversityTiruchirappalli 620024India

recently,anomaly detection(AD)in streaming data gained significant attention among research communities due to its applicability in finance,business,healthcare,education,etc.The recent developments of deep learning(DL)models find helpful in the detection and classification of anomalies.This article designs an oversampling with an optimal deep learning-based streaming data classification(Os-ODLsDC)model.The aim of the OsODLsDC model is to recognize and classify the presence of anomalies in the streaming data.The proposed Os-ODLsDC model initially undergoes preprocessing step.since streaming data is unbalanced,support vector machine(sVM)-synthetic Minority Over-sampling Technique(sVM-sMOTE)is applied for oversampling process.Besides,the Os-ODLsDC model employs bidirectional long short-term memory(Bi LsTM)for AD and classification.Finally,the root means square propagation(rMsProp)optimizer is applied for optimal hyperparameter tuning of the Bi LsTM model.For ensuring the promising performance of the Os-ODLsDC model,a wide-ranging experimental analysis is performed using three benchmark datasets such as CICIDs 2018,KDD-Cup 1999,and NsL-KDD datasets.

关键词： anomaly detection deep learning hyperparameter optimization oversampling sMOTE streaming data

Parametric investigation on the novel and cost-effective nano fly ash impregnated geopolymer system for sustainable construction

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Frontiers of structural and Civil Engineering 2024年第2期18卷 170-183页

作者： r.MOHANA s.M.Leela BHArATHI Department of Civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction industry.The development of geopolymer structures provides a way of producing 100%cement-free construction.In this research work,a novel and simple way of deriving nano particles from waste fly ash particles is promoted.The effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by considering strength and durability properties.Parameter optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder content.From the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer medium.This can explain the extraordinary gain in strength of 72.11 MPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration durability polymerization fillers

Managing type 2 diabetes:targeting a microbial enzyme as a novel treatment option

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signal Transduction and Targeted Therapy 2024年第1期9卷 3-5页

作者： Anikó Keller-Pintér Tamás Korcsmáros Tibor Vellai Department of Biochemistry Albert Szent-Györgyi Medical SchoolUniversity of SzegedSzeged6720Hungary Department of Metabolism Digestion and ReproductionImperial College LondonLondonW120NNUK Quadram Institute Bioscience Norwich Research ParkNorwichNR47UQUK Department of Genetics Eötvös Loránd University(ELTE)Budapest1117Hungary Hungarian research Network HUN-rEN-ELTE Genetics research Group Budapest1117Hungary

In a recent science article,Wang and colleagues showed that the dipeptidyl peptidase 4(DPP4)enzyme produced by the gut microbiota can interfere with the effect of host glucagon-like peptide-1(GLP-1)involved in stimulating insulin secretion,and the specific inhibitor of microbial DPP4(mDPP4),combined with clinical inhibitors of host DPP4 isoenzymes,further promotes blood glucose homeostasis.1 These results point out why certain patients respond inadequately to an antidiabetic medication.

关键词： homeostasis stimulating clinical

Use of Patient-specific “4D” Tele-Education to Enhance Actual and Perceived Knowledge in Congenital Heart Disease (CHD) Patients

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Congenital Heart Disease 2024年第1期19卷 5-17页

作者： Molly Clarke Karin Hamann Nancy klein Laura Olivieri Yue-Hin Loke Department of Inpatient Cardiology Boston Children’s HospitalBoston02115USA Department of Cardiology Children’s National HospitalWashington20001USA Department of Cardiology Noninvasive Cardiac ImagingUniversity of Pittsburgh Medical Center Children’s Hospital of PittsburghPittsburgh15224USA

Background:Patients with congenital heart disease(CHD)will transition to lifelong adult congenital cardiac care.However,their structural heart disease is challenging to convey via two-dimensional drawings.This study utilized a tele-educational environment,with personalized three-dimensional(3D)modeling and health Details(3D+Details=“4D”),to improve actual and perceived knowledge,both important components of transition readiness in CHD patients.Methods:Participants aged≥13 years with a history of CHD and cardiac magnetic resonance imaging(MrI)studies were eligible.Cardiac MrI datasets were then used to segment and create 3D heart models(using Mimics,Materialize Inc.).Participantsﬁrst completed the MyHeart Questionnaire,a validated survey of actual knowledge.A tele-educational session was then scheduled,during which participants were shown a 3D model of a normal heart,followed by their personal 3D heart model and speciﬁc health details.Participants then repeated the actual knowledge survey,in addition to questionnaires assessing perceived knowledge pre-and post-session,as well as a satisfaction survey.results:Twenty-two patients were included.Actual knowledge increased from 75%±15%to 89%±20%(p=0.00043)and perceived knowledge increased inﬁve of seven questions.Actual knowledge correlated with perceived knowledge(r=0.608,prcent of participants ranked the 3D model as“very satisfactory”and ninety-ﬁve percent ranked the educational session as“very help-ful”or“extremely helpful.”Conclusions:The use of“4D”tele-education increased both actual and perceived knowledge and may help improve transition readiness in CHD patients.

关键词： Congenital heart disease tele-education transition

Limited impacts of occasional tillage on dry aggregate size distribution and soil carbon and nitrogen fractions in semi-arid drylands

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International soil and Water Conservation research 2024年第1期12卷 96-106页

作者： Wooiklee s.Paye Vesh r.Thapa rajan Ghimire New Mexico state University Agricultural Science CenterClovisNM88101USA New Mexico state University Department of Plant and Environmental SciencesLas CrucesNM88003USA

Tillage management that minimizes the frequency and intensity of soil disturbance can increase soil carbon(C)and nitrogen(N)sequestration and improve the resilience of dryland cropping systems,yet the impact of occasional disturbance on soil aggregate formation and the soil organic carbon(sOC)storage within aggregates has not been studied well.We evaluated the effect of four tillage management practices on soil dry aggregate size distribution,aggregate-protected C and N,mineral-associated organic matter carbon(MAOM-C),particulate organic matter carbon(POM-C),and corn(Zea mays L.)and sorghum(sorghum bicolor(L.)Moench)yields in a semi-arid dryland cropping system.Treatments included conventional tillage(CT),strip-tillage(sT),no-tillage(NT),and occasional tillage(OT)management in a corn-sorghum rotation.soil macro-aggregates were 51-54%greater under sT,NT,and OT,while small and micro-aggregates were greater in CT.Conventional tillage reduced soil aggregate-associated C by 28-31%in macro-aggregates and 47-53%in small aggregates at 26 months(M)sampling compared to sT,NT,and OT.In clay+silt fraction,CT had 14-16%,21-26%,and 36-43%less sOC at 7,14,and 26M samplings,respectively,than sT,NT,and OT.Aggregate associated N was generally similar under sT,NT,and OT,which was greater on average than CT.soil MOAM-C and POM-C under sT,NT,and OT were generally greater than respective sOC fractions under CT at 19 and 26 M after OT implementation.Corn and sorghum yields were similar among tillage systems in 2020,but greater under sT,NT,and OT than CT in 2021.Our results suggest that while frequent intensive tillage can lower sOC and N storage,a single stubble mulch occasional tillage after several years of NT does not lead to soil C and N losses and soil structural instability in semi-arid drylands.

关键词： Conventional tillage Occasional tillage Aggregate associated carbon Mineral associated organic matter carbon(MAOM-C) Particulate organic matter carbon(POM-C)

Enhancing XrF sensor-based sorting of porphyritic copper ore using particle swarm optimization-support vector machine(PsO-sVM)algorithm

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International Journal of Mining science and Technology 2024年第4期34卷 545-556页

作者： Zhengyu Liu Jue Kou Zengxin Yan Peilong Wang Chang Liu Chunbao sun Anlin shao Bern klein school of Civil and resources Engineering University of Science and TechnologyBeijing 100083China Institute of Minerals research University of Science and TechnologyBeijing 100083China state Key Laboratory of Mineral Processing Beijing 102628China Ansteel Group Mining Co.Ltd. Anshan 114000China Norman B.Keevil Institute of Mining Engineering University of British ColumbiaVancouverBC V6T 1Z4Canada

X-ray fluorescence(XrF)sensor-based ore sorting enables efficient beneficiation of heterogeneous ores,while intraparticle heterogeneity can cause significant grade detection errors,leading to misclassifications and hindering widespread technology adoption.Accurate classification models are crucial to determine if actual grade exceeds the sorting threshold using localized XrF signals.Previous studies mainly used linear regression(Lr)algorithms including simple linear regression(sLr),multivariable linear regression(MLr),and multivariable linear regression with interaction(MLrI)but often fell short attaining satisfactory results.This study employed the particle swarm optimization support vector machine(PsO-sVM)algorithm for sorting porphyritic copper ore pebble.Lab-scale results showed PsO-sVM out-performed Lr and raw data(rD)models and the significant interaction effects among input features was observed.Despite poor input data quality,PsO-sVM demonstrated exceptional capabilities.Lab-scale sorting achieved 93.0%accuracy,0.24%grade increase,84.94%recovery rate,57.02%discard rate,and a remarkable 39.62 yuan/t net smelter return(Nsr)increase compared to no sorting.These improvements were achieved by the PsO-sVM model with optimized input combinations and highest data quality(T=10,T is XrF testing times).The unsuitability of Lr methods for XrF sensor-based sorting of investigated sample is illustrated.Input element selection and mineral association analysis elucidate element importance and influence mechanisms.

关键词： XrF sensor-based sorting PsO-sVM algorithm Copper ore pebble receiver operating curve(rOC) Net smelter return(Nsr)