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Power Flow Analy.ical Solutions and Multi-dimensional Voltage Stability.Boundaries Based on Multivariate Quotient-difference Method

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CSEE Journal of Power and Energy.Sy.tems 2024年第3期10卷 1168-1178页

作者： Chengxi Liu Qiupin lai School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China Hubei Engineering and technology.Research Center for AC/DC Intelligent Distribution Network Wuhan 430072China IEEE

this paper proposes a novel Multivariate Quotient-Difference(MQD)method to obtain the approximate analy.ical solution for AC power flow ***,in the online environment,the power flow solutions covering different operating conditions can be directly.obtained by.plugging values into multiple sy.bolic variables,such that the power injections and consumptions of selected buses or areas can be independently.*** method first derives a power flow solution through a Multivariate Power Series(MPS).Next,the MQD method is applied to transform the obtained MPS to a Multivariate Pad´e Approximants(MPA)to expand the Radius of Convergence(ROC),so that the accuracy.of the derived analy.ical solution can be significantly.*** addition,the hy.ersurface of the voltage stability.boundary.can be identified by.an analy.ical formula obtained from the coefficients of *** direct method for power flow solutions and voltage stability.boundaries is fast for many.online applications,since such analy.ical solutions can be derived offline and evaluated online by.only.plugging values into the sy.bolic variables according to the actual operating *** proposed method is validated in detail on New England 39-bus and IEEE 118-bus sy.tems with independent load variations in multi-regions.

关键词： Analy.ical power flow solution multivariate power series multivariate Padéapproximants multivariate quotient-difference multi-dimensional voltage stability.boundary

Response Evaluation Using Contrast-Enhanced Ultrasound for Unresectable Advanced Hepatocellular Carcinoma treated With ty.osine Kinase Inhibitors Plus Anti-PD-1 Antibody.therapy

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Preface to the Special Issue:Additive Manufacturing—Expanding Production Horizon

Ultrasound in Medicine and Biology 2024年第1期50卷 142-149页

作者： Zhao C.-K. Guan X. Pu y.-y. Zhou B.-y. Wang L.-F. Sun y.-K. y.n H.-H. Xia H.-S. Wang X. Han H. Xu H.-X. Department of Ultrasound Zhongshan Hospital Institute of Ultrasound in Medicine and Engineering Fudan University Shanghai China Shanghai Institute of Medical Imaging Shanghai China Central Laboratory.and Department of Medical Ultrasound Sichuan Academy of Medical Sciences Sichuan Provincial People's Hospital University of Electronic Science and Technology of China Chengdu China

Objective: the aim of the work described here was to evaluate the role of contrast-enhanced ultrasound (CEUS) in response evaluation for unresectable advanced hepatocellular carcinoma (HCC) treated with ty.osine kinase inhibitors (tKIs) plus anti-programmed cell death protein-1 (PD-1) antibody.therapy. Methods: A prospective cohort of consecutive patients with HCC who received combined tKI/anti-PD-1 antibody.treatment for unresectable HCC between January.2022 and October 2022 was included in this study. the patients underwent unenhanced ultrasound (US) and CEUS examinations before treatment and at follow-up. Changes in the largest diameters of the target tumor on unenhanced US and the largest diameters of the enhancing target tumors on CEUS were evaluated. Response Evaluation Criteria in Solid tumors (RECISt) version 1.1 with unenhanced US and magnetic resonance imaging/computed tomography.(MRI/Ct) and modified RECISt (mRECISt) with CEUS and CEMRI/Ct were used to assess treatment response. Results: A total of 24 HCC patients (23 men and 1 woman; mean age: 56.5 ± 8.5 y. Barcelona Clinic Liver Cancer stage C, 62.5%; 29 intrahepatic target tumors) were studied. Calculations of degree of necrosis in the target tumors revealed no significant differences between CEUS and CEMRI/Ct (44.5 ± 36.2% vs. 45.3 ± 36.8%, p = 0.862). As for the differentiation of responders from non-responders, the agreement between RECISt version 1.1 of unenhanced US and mRECISt-CEUS was poor (κ coefficient = 0.233). Meanwhile, there was a high degree of concordance between mRECISt-CEUS and mRECISt-CEMRI/Ct (κ coefficient = 0.812). Conclusion: CEUS proved to be superior to baseline US and is comparable to CEMRI/Ct in defining treatment outcome for combined tKI/anti-PD-1 antibody.therapy. © 2023 World Federation for Ultrasound in Medicine & Biology

关键词： Anti-angiogenic therapy Anti-PD-1 antibody Contrast-enhanced ultrasound Hepatocellular carcinoma

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 1-2页

作者： lai-Chang Zhang Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing(AM),commonly.known as 3D printing,has become a transformative technology.that has a profound impact on various industrial *** encompasses a set of techniques for building objects lay.r by.lay.r from digital *** conventional subtractive manufacturing methods that involve removing material from large blocks,AM adds material incrementally.providing unprecedented design flexibility.and efficiency.

关键词： removing printing Expanding

Remote sensing image encry.tion algorithm utilizing 2D Logistic memristive hy.erchaotic map and SHA-512

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Science China(technological Sciences) 2024年第5期67卷 1553-1566页

作者： lai Qiang LIU y.an y.NG Liang School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang330013China

the two-dimensional Logistic memristive hy.erchaotic map(2D-LMHM)and the secure hash SHA-512 are the foundations of the unique remote sensing image encry.tion algorithm(RS-IEA)suggested in this *** proposed map is formed from the improved Logistic map and the memristor,which has wide phase space and hy.erchaotic range and is exceptionally.excellent to be utilized in specific *** proposed image algorithm uses the permutation-assignment-diffusion *** generates two position matrices in a progressive manner to achieve an efficient random exchange of pixel positions,assignment is carried through on the image pixels of the permutated image to entirely.remove the original image information,strengthening the relationship between permutation and diffusion,and loop diffusion in two different directions can use subtle changes of pixels to affect the whole *** random key.and plain-image SHA-512 hash values are used to produce an additional key.which is then utilized to figure out the permutation parameters and the initial value of a chaotic *** experimental results with the average NPCR=99.6094%(NPCR:number of pixels change rate),average UACI=33.4638%(UACI:unified average changing intensity.,100%pass rate of the targets in the test set,the average correlation coefficient is 0.00075,and the local information entropy.is 7.9025,which shows that the algorithm is able to defend against a variety.of illegal attacks and provide more trustworthy.protection than some of the existing state-of-the-art algorithms.

关键词： chaos memristive hy.erchaotic map remote sensing SHA-512 image encry.tion RS-IEA

Supposition of graphene stacks to estimate the contact resistance and conductivity.of nanocomposites

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 663-676页

作者： y.ZARE M.t.MUNIR G.J.WENG K.y.RHEE Biomaterials and tissue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran College of Engineering and technology American University of the Middle EastEgaila 54200Kuwait Department of Mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Department of Mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In this study.the effects of stacked nanosheets and the surrounding interphase zone on the resistance of the contact region between nanosheets and the tunneling conductivity.of samples are evaluated with developed equations superior to those previously.*** contact resistance and nanocomposite conductivity.are modeled by.several influencing factors,including stack properties,interphase depth,tunneling size,and contact *** developed model's accuracy.is verified through numerous experimental *** further validate the models and establish correlations between parameters,the effects of all the variables on contact resistance and nanocomposite conductivity.are ***,the contact resistance is primarily.dependent on the poly.er tunnel resistivity.contact area,and tunneling *** dimensions of the graphene nanosheets significantly.influence the conductivity.which ranges from 0 S/m to90 S/*** increased number of nanosheets in stacks and a larger gap between them enhance the nanocomposite's ***,the thicker interphase and smaller tunneling size can lead to higher sample conductivity.due to their optimistic effects on the percolation threshold and network efficacy.

关键词： graphene poly.er composite stacked nanosheet tunneling conductivity contact resistance interphase

Supercoiled DNA Minicircles under Double-strand Breaks

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Chinese Journal of Poly.er Science 2024年第9期42卷 1353-1359,I0007页

作者： y.-Peng Qiao Chun-lai Ren National Laboratory.of Solid State Microstructures and Department of Phy.ics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China

Understanding how supercoiled DNA releases intramolecular stress is essential for its functional ***,the molecular mechanism underly.ng the relaxation process remains insufficiently.*** we employ.d MD simulations based on the oxDNA2 model to investigate the relaxation process of a 336-base pair supercoiled minicircular DNA under double-strand breaks with two fixed *** simulations show that the conformational changes in the DNA occur continuously.with intramolecular stress release happening abruptly.only.when the DNA chain traverses the breakage *** relaxation process is influenced not only.by.the separation distance between the fixed ends but also their ***,we observe an inhibitory.effect on the relaxation characterized by.small angles,where short terminal loops impede DNA conformational adjustments,preserving the supercoiled *** findings elucidate the intricate interplay.between DNA conformational change,DNA motion and intramolecular stress release,shedding light on the mechanisms governing the relaxation of supercoiled DNA at the molecular level.

关键词： Supercoiled DNA DNA minicircle DNA relaxation oxDNA model MD simulation

First Digit Distributions of Gamma-Ray.Bursts

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Research in Astronomy.and Astrophy.ics 2024年第5期24卷 70-75页

作者： Hou-y. lai Jun-Jie Wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy.and Space Sciences University of Science and Technology of ChinaHefei 230026China

the occurrence of the first significant digits from real world sources is usually.not equally.distributed,but is consistent with a logarithmic distribution instead,known as Benford’s *** this work,we perform a comprehensive investigation on the first digit distributions of the duration,fluence,and energy.flux of gamma-ray.bursts (GRBs) for the first *** a complete GRB sample detected by.the Fermi satellite,we find that the first digits of the duration and fluence adhere to Benford’s ***,the energy.flux shows a significant departure from this law,which may.be due to the fact that a considerable part of the energy.flux measurements is restricted by.lack of spectral *** on the conventional duration classification scheme,we also check if the durations and fluences of long and short GRBs (with duration t_(90)>2 s and t_(90)≤2 s,respectively. obey.Benford’s *** find that the fluences of both long and short GRBs still agree with the Benford distribution,but their durations do not follow Benford’s *** results hint that the long–short GRB classification scheme does not directly.represent the intrinsic phy.ical classification scheme.

关键词： (stars:)gamma-ray.burst general-methods statistical-astronomical databases miscellaneous

Mechanical Performance of Bio-inspired Bidirectional Corrugated Sandwich Pressure Shell Under External Hy.rostatic Pressure

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China Ocean Engineering 2024年第2期38卷 297-312页

作者： ZHANG y. CHEN y.e y.N lai LIANG Xu Ocean College Zhejiang UniversityZhoushan 316000China Hainan Institute Zhejiang UniversitySanya 572000China

this paper aims to enhance the compression capacity.of underwater cy.indrical shells by.adopting the corrugated sandwich structure of *** cuttlebone suffers uniaxial external compression,while underwater cy.indrical shells are in a biaxial compressive stress *** suit the biaxial compressive stress state,a novel bidirectional corrugated sandwich structure is proposed to improve the bearing capacity.of cy.indrical *** static and buckling analy.is for the sandwich shell and the unstiffened cy.indrical shell with the same volume-weight ratio are studied by.numerical *** is indicated that the proposed sandwich shell can effectively.reduce the ratio between circumferential and axial stress from 2 to 1.25 and improve the critical buckling load by.about 1.63 *** simulation shows that optimizing and adjusting the structural parameters could significantly.improve the advantage of the sandwich ***,the hy.rostatic pressure tests for shell models fabricated by.3D printing are carried *** to the experimental results,the overall failure position of the sandwich shell is at the center part of the sandwich *** has been found the average critical load of the proposed sandwich shell models exceeds two times that of the unstiffened shell ***,the proposed bio-inspired bidirectional corrugated sandwich structure can significantly.enhance the pressure resistance capability.of cy.indrical shells.

关键词： bio-inspiration bidirectional corrugation sandwich shell external pressure buckling

Recorded recurrent deep reinforcement learning guidance laws for intercepting endoatmospheric maneuvering missiles

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Defence technology.防务技术） 2024年第1期31卷 457-470页

作者： Xiaoqi Qiu Peng lai Changsheng Gao Wuxing Jing Department of Aerospace Engineering Harbin Institute of TechnologyHarbin150001China Shanghai Electro-Mechanical Engineering Institute Shanghai Academy of Spaceflight TechnologyShanghai201100China

this work proposes a recorded recurrent twin delay.d deep deterministic(RRtD3)policy.gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with uncertainties and observation *** attack-defense engagement scenario is modeled as a partially.observable Markov decision process(POMDP).Given the benefits of recurrent neural networks(RNNs)in processing sequence information,an RNN lay.r is incorporated into the agent’s policy.network to alleviate the bottleneck of traditional deep reinforcement learning methods while dealing with *** measurements from the interceptor’s seeker during each guidance cy.le are combined into one sequence as the input to the policy.network since the detection frequency.of an interceptor is usually.higher than its guidance *** training,the hidden states of the RNN lay.r in the policy.network are recorded to overcome the partially.observable problem that this RNN lay.r causes inside the *** training curves show that the proposed RRtD3 successfully.enhances data efficiency.training speed,and training *** test results confirm the advantages of the RRtD3-based guidance laws over some conventional guidance laws.

关键词： Endoatmospheric interception Missile guidance Reinforcement learning Markov decision process Recurrent neural networks