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Starlet:Network defense resource allocation with multi-armed bandits for cloud-edge crowd sensing in IoT

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Digital Communications and Networks 2024年第3期10卷 586-596页

作者： Hui xia Ning Huang Xuecai Feng Rui Zhang Chao liu College of Computer Science and Technology Ocean University of ChinaQingdao266100China

The cloud platform has limited defense resources to fully protect the edge servers used to process crowd sensing data in Internet of *** guarantee the network's overall security,we present a network defense resource allocation with multi-armed bandits to maximize the network's overall ***,we propose the method for dynamic setting of node defense resource thresholds to obtain the defender(attacker)benefit function of edge servers(nodes)and ***,we design a defense resource sharing mechanism for neighboring nodes to obtain the defense capability of ***,we use the decomposability and Lipschitz conti-nuity of the defender's total expected utility to reduce the difference between the utility's discrete and continuous arms and analyze the difference ***,experimental results show that the method maximizes the defender's total expected utility and reduces the difference between the discrete and continuous arms of the utility.

关键词： Internet of things Defense resource sharing Multi-armed bandits Defense resource allocation

An active learning workflow for predicting hydrogen atom adsorption energies on binary oxides based on local electronic transfer features

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Green Energy & Environment 2024年第10期9卷 1489-1496页

作者： Wenhao Jing Zihao Jiao Mengmeng Song ya liu Liejin Guo International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Department of Energy and Power Engineering Shandong University of Technology

Machine learning combined with density functional theory（DFT） enables rapid exploration of catalyst descriptors space such as adsorption energy, facilitating rapid and effective catalyst screening. However, there is still a lack of models for predicting adsorption energies on oxides,due to the complexity of elemental species and the ambiguous coordination environment. This work proposes an active learning workflow（Le NN） founded on local electronic transfer features（e） and the principle of coordinate rotation invariance. By accurately characterizing the electron transfer to adsorption site atoms and their surrounding geometric structures, Le NN mitigates abrupt feature changes due to different element types and clarifies coordination environments. As a result, it enables the prediction of *H adsorption energy on binary oxide surfaces with a mean absolute error（MAE） below 0.18 e V. Moreover, we incorporate local coverage（θl） and leverage neutral network ensemble to establish an active learning workflow, attaining a prediction MAE below 0.2 e V for 5419 multi-*H adsorption structures. These findings validate the universality and capability of the proposed features in predicting *H adsorption energy on binary oxide surfaces.

关键词： Machine learning Adsorption energy Binary oxide Electron transfer Active learning

Mathematical Analysis on a General Delayed HBV Model with Capsids and Two Infection Routes

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 508-525页

作者： Li-li liu Hong-gang WANG ya-zhi LI Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention Complex Systems Research CenterShanxi UniversityTaiyuan 030006China School of Mathematics and Statistics Qiannan Normal University for NationalitiesDuyun 558000China

Considering that HBV belongs to the DNA virus family and is hepatotropic,we model the HBV DNA-containing capsids as a *** this paper,a delayed HBV infection model is established,where the general incidence function and two infection routes including cell-virus infection and cell-cell infection are *** to some preliminaries,including well-posedness,basic reproduction number and existence of two equilibria,we obtain the threshold dynamics for the *** illustrate numerical simulations to verify the above theoretical results,and furthermore explore the impacts of intracellular delay and cell-cell infection on the global dynamics of the model.

关键词： delayed HBV model capsids general incidence function two infection routes global stability

Symmetry of upper eyelid after unilateral blepharoptosis repair with minimally invasive conjoint fascial sheath suspension technique

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 53-60页

作者： Yianzhu liu Wenli Chen xia Chen Tianjin Eye Hospital Tianjin 300020China Tianjin Key Lab of Ophthalmology and Visual Science Tianjin 300020China

AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)***:A retrospective study of patients who underwent unilateral minimally invasive CFS suspension surgery between January 2018 and December *** criteria included unilateral mild and moderate ptosis,good levator muscle function(>9 mm)and follow-up of at least ***-and post-operative symmetry was graded subjectively for marginal reflex distance 1(MRD1),tarsal platform show(TPS)and eyebrow fat span(BFS).A t-test was used to evaluate MRD1,TPS and BFS asymmetry by calculating delta *** Bézier curve tool of the Image J software was used to extract the upper eyelid contours,where the symmetry was measured by the percentage of overlapping curvatures(POC).RESULTS:Totally 105 patients(105 eyelids)were included(mild group,n=84;moderate group,n=21).Postoperatively,all patients increased MRD1 and decreased TPS in the ptotic eye while maintaining unchanged *** asymmetric delta value for MRD1 was measured to be 1.48±0.86 preoperatively,and it decreased to 0.58±0.67 postoperatively in all cases(P=0.0004).In patients with mild ptosis,the asymmetry value of TPS fell significantly from 1.15±0.62 to 0.68±0.38(P=0.0187).The symmetry of the upper eyelid contour increased in all subgroups of patients,with a POC of 59.39%±13.45%preoperatively and POC of 78.29%±13.80%***:Minimally invasive CFS suspension is proved to be an effective means of improving the symmetry of unilateral ptosis in terms of MRD1(all subgroups),POC(all subgroups)and TPS(only mild group),whereas BFS is unaffected.

关键词： symmetry unilateral blepharoptosis minimally invasive combined fascia sheath suspension

Effects of intensive psychological intervention on treatment compliance,psychological status,and quality of life of patients with epilepsy

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World Journal of Psychiatry 2024年第5期14卷 670-677页

作者： Su-Hua Zhang Jie-Hua Wang Hong-Yu liu Yue-xia Zhang ya-Ling Lin Bi-Yu Wu Department of Neurology Quanzhou First HospitalQuanzhou 362000Fujian ProvinceChina Department of Nursing Quanzhou First HospitalQuanzhou 362000Fujian ProvinceChina

BACKGROUND Epilepsy is a nervous system disease characterized by recurrent attacks,a long disease course,and an unfavorable *** is associated with an enduring therapeutic process,and finding a cure has been *** with epilepsy are predisposed to adverse moods,such as resistance,anxiety,nervousness,and anxiety,which compromise treatment compliance and overall *** To explored the influence of intensive psychological intervention on treatment compliance,psychological status,and quality of life(QOL)of patients with *** The clinical data of 105 patients with epilepsy admitted between December 2019 and July 2023 were retrospectively analyzed,including those of 50 patients who underwent routine intervention(control group)and 55 who underwent intensive psychological intervention(research group).Treatment compliance,psychological status based on the Self-Rating Anxiety Scale(SAS)and Depression Scale Self-Rating Depression Scale(SDS)scores,hope level assessed using the Herth Hope Scale(HHS),psychological resilience evaluated using the Psychological Resilience Scale,and QOL determined using the QOL in Epilepsy-31 Inventory(QOLIE-31)were comparatively *** Treatment compliance in the research group was 85.5%,which is significantly better than the 68.0%of the control *** notable intergroup differences in preinterventional SAS and SDS scores were identified(P>0.05);however,after the intervention,the SAS and SDS scores decreased significantly in the two groups,especially in the research group(P0.05).After 6 months of intervention,the research group showed evidently higher HHS,CD-RISC,tenacity,optimism,strength,and QOLIE-31 scores(P<0.05).CONCLUSION Intensive psychological intervention enhances treatment compliance,psychological status,and QOL of patients with epilepsy.

关键词： Intensive psychological intervention Epilepsy Treatment compliance Psychological status Quality of life

Estimating shear strength of high-level pillars supported with cemented backfilling using the HoekeBrown strength criterion

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 454-469页

作者： Kaizong xia Congxin Chen Xiumin liu Yue Wang Xuanting liu Jiahao Yuan State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Deep metal mines are often mined using the high-level pillars with subsequent cementation backfilling(HLSCB)mining *** the design stage,it is therefore important to have a reasonable method for determining the shear strength of the high-level pillars(*** and internal friction angle)when they are supported by cemented *** this study,a formula was derived for the upper limit of the confining pressure σ3max on a high-level pillar supported by cemented backfilling in a deep metal mine.A new method of estimating the shear strength of such pillars was then proposed based on the Hoek eBrown failure *** analysis indicates that the horizontal stress σhh acting on the cemented backfill pillar can be simplified by expressing it as a constant value.A reasonable and effective value for σ3max can then be *** value of s3max predicted using the proposed method is generally less than 3 *** this range,the shear strength of the high-level pillar is accurately calculated using the equivalent MohreCoulomb *** proposed method can effectively avoid the calculation of inaccurate shear strength values for the high-level pillars when the original HoekeBrown criterion is used in the presence of large confining pressures,*** situation in which the cohesion value is too large and the friction angle is too small can effectively be *** proposed method is applied to a deep metal mine in China that is being excavated using the HLSCB *** shear strength parameters of the high-level pillars obtained using the proposed method were input in the numerical *** numerical results show that the recommended level heights and sizes of the high-level pillars and rooms in the mine are rational.

关键词： Deep metal mines High-level pillars HoekeBrown strength criterion Cemented backfilling Confining pressure Shear strength

Carbon fiber reinforced liquid crystalline elastomer composites:a dual exploration in strength augmentation and transformation flexibility through 4D printing

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International Journal of Smart and Nano Materials 2024年第2期15卷 312-329页

作者： Yuliang xia Tong Mu yanju liu Jinsong Leng Centre for Composite Materials and Structures Harbin Institute of Technology(HIT)HarbinPeople's Republic of China Department of Astronautical Science and Mechanics Harbin Institute of Technology(HIT)HarbinPeople's Republic of China

Liquid Crystal Elastomers(LCEs)are renowned for their reversible deformation ***,enhancing their mechanical strength while retaining such flexibility has posed a considerable *** overcome this,we utilized 4D printing to develop an innovative composite of LCE with carbon fiber fabric(LCEC).This approach has notably increased the tensile strength of LCE by eightfold,all the while maintaining its exceptional capacity for reversible *** adjusting the alignment angle between carbon fiber and the LCE printing direction from 0°to 90°,the LCEC demonstrates an array of new deformation patterns,including bending,twisting,wrapping,and S-shaped transformations,which are distinct from pure LCE *** study unveils that LCE composites exhibit deformation processes markedly different from their pure material counterparts,with the ability of pure LCE to sustain tensile strains exceeding 1900%.These findings,previously undocumented and unexplored,represent a substantial contribution to the field of smart *** finite element analysis,we explored the carbon fiber and LcE matrix dynamics,revealing bending mechanics in *** combined experimental and simulation approach yields crucial insights for crafting durable,high-strength LCECs with diverse deformational properties,advancing smart material technology.

关键词： Liquid crystal elastomer composites 4D printing Smart materials

Three dimensional discrete element modelling of the conventional compression behavior of gas hydrate bearing coal

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International Journal of Coal Science & Technology 2024年第1期11卷 61-77页

作者： xia Gao Nannan Wang Baoyong Zhang Qiqi Lin Qiang Wu Wei Meng xia liu Department of Architecture and Civil Engineering Heilongjiang University of Science and TechnologyHarbin150022China School of Qilu Transportation Shandong UniversityJinan250061China Department of Safety Engineering Heilongjiang University of Science and TechnologyHarbin150022China Jining Hongxiang Highway Survey Design and Research Institute Co.Ltd Jining272000China

To analyze the relationship between macro and meso parameters of the gas hydrate bearing coal(GHBC)and to calibrate the meso-parameters,the numerical tests were conducted to simulate the laboratory triaxial compression tests by PFC3D,with the parallel bond model employed as the particle contact constitutive ***,twenty simulation tests were conducted to quantify the relationship between the macro–meso ***,nine orthogonal simulation tests were performed using four meso-mechanical parameters in a three-level to evaluate the sensitivity of the meso-mechanical ***,the calibration method of the meso-parameters were then ***,the contact force chain,the contact force and the contact number were examined to investigate the saturation effect on the meso-mechanical behavior of *** results show that:(1)The elastic modulus linearly increases with the bonding stiffness ratio and the friction coefficient while exponentially increasing with the normal bonding strength and the bonding radius *** failure strength increases exponentially with the increase of the friction coefficient,the normal bonding strength and the bonding radius coefficient,and remains constant with the increase of bond stiffness ratio;(2)The friction coefficient and the bond radius coefficient are most sensitive to the elastic modulus and the failure strength;(3)The number of the force chains,the contact force,and the bond strength between particles will increase with the increase of the hydrate saturation,which leads to the larger failure strength.

关键词： Gas hydrate bearing coal Discrete element method Triaxial compression test Macro-meso mechanical propertie

Sensitivity analyses of random cave groups on karst tunnel stability based on water–rock interaction using a novel contact dynamic method

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Underground Space 2024年第5期18卷 162-186页

作者： Chengzhi xia Zhenming Shi Huanjia Kou Shaoqiang Meng Maomao liu College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

This paper concentrates on the sensitivity and dynamic simulation of randomly distributed karst cave groups on tunnel stability and connectivity extended ratio based on water–rock interaction using a novel contact dynamic method(CDM).The concept of karst cave group connectivity extended ratio during tunneling and water inrush is *** effects of cave shape and spatial distribution on Qiyueshan tunnel are *** deformation and damage index,and connectivity extended ratio with uniform random karst cave groups are *** results demonstrate that the connectivity extended ratio is verified as a crucial judgment in predicting the safe distance and assessing the stability of the tunnel with the karst cave *** model captures the fracture propagation and contact behavior of rock mass,surface flow,as well as the bidirectional water–rock interaction during the water inrush of Qiyueshan tunnel with multiple caves.A larger cave radius and smaller minimum distance between the cave and tunnel increase the deformation and damage index of the surrounding *** the cave radius and cave area ratio increase,the failure pattern shifts from overall to local *** findings potentially have broad applications in various surface and subsurface scenarios involving water–rock interactions.

关键词： Karst tunnel stability Contact dynamic method Connectivity extended ratio Karst cave groups Qiyueshan tunnel Water-rock interaction