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Effect of hollow insulation riser on shrinkage porosity and solidification structure of ingot

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Journal of Iron and Steel Research(International) 2022年第12期29卷 1951-1960页

作者： Ying-jie Liu Chun-lin Peng Wan-ming Li Xiao-lei Zhu Ming-gang Shen xiang-wei liao Kun Liu Chong-yi wei Yusuf Abba Yusuf Ji Yang Chang-you Cai School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114000LiaoningChina

The thermal insulation performance of riser is very important to the shrinkage porosity and solidification structure of ingot,but it is difficult to significantly improve due to the limit of thermal conductivity of riser material.A new type of hollow insulation riser was proposed based on the low thermal conductivity of air,which aims to improve the thermal insulation performance of riser.A 14.5-t steel ingot was prepared using the hollow insulation riser,and the casting temperature was 1500°*** temperature evolution of the external surface of mold during solidification was measured using an infrared temperature instrument.A numerical model was established to simulate the porosity and solidification structure of *** reliability of numerical simulation was verified by comparing simulation and experimental *** show that the insulation performance of the riser can be significantly improved through application of the hollow insulation *** with solid insulation sleeve,the shrinkage cavity depth was decreased and the position of porosity was raised when hollow insulation riser was applied.

关键词： Hollow insulation riser Solidification Heat transfer Porosity Thermal conductivity

Towards sustainable adversarial training with successive perturbation generation

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 527-539页

作者： wei LIN Lichuan liao College of Computer Science and Mathematics Fujian University of TechnologyFuzhou 350118China College of Economics and Management Xi’an University of TechnologyXi’an 710048China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou 350118China

Adversarial training with online-generated adversarial examples has achieved promising performance in defending adversarial attacks and improving robustness of convolutional neural network ***,most existing adversarial training methods are dedicated to finding strong adversarial examples for forcing the model to learn the adversarial data distribution,which inevitably imposes a large computational overhead and results in a decrease in the generalization performance on clean *** this paper,we show that progressively enhancing the adversarial strength of adversarial examples across training epochs can effectively improve the model robustness,and appropriate model shifting can preserve the generalization performance of models in conjunction with negligible computational *** this end,we propose a successive perturbation generation scheme for adversarial training(SPGAT),which progressively strengthens the adversarial examples by adding the perturbations on adversarial examples transferred from the previous epoch and shifts models across the epochs to improve the efficiency of adversarial *** proposed SPGAT is both efficient and effective;e.g.,the computation time of our method is 900 min as against the 4100 min duration observed in the case of standard adversarial training,and the performance boost is more than 7%and 3%in terms of adversarial accuracy and clean accuracy,*** extensively evaluate the SPGAT on various datasets,including small-scale MNIST,middle-scale CIFAR-10,and large-scale *** experimental results show that our method is more efficient while performing favorably against state-of-the-art methods.

关键词： Adversarial training Adversarial attack Stochastic weight average Machine learning Model generalization

Practical cloud storage auditing using serverless computing

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Science China(Information Sciences) 2024年第3期67卷 33-47页

作者： Fei CHEN Jianquan CAI Tao xiang Xiaofeng liao College of Computer Science and Software Engineering Shenzhen University College of Computer Science Chongqing University

Cloud storage auditing research is dedicated to solving the data integrity problem of outsourced storage on the cloud. In recent years, researchers have proposed various cloud storage auditing schemes using different techniques. While these studies are elegant in theory, they assume an ideal cloud storage model;that is, they assume that the cloud provides the storage and compute interfaces as required by the proposed schemes. However, this does not hold for mainstream cloud storage systems because these systems only provide read and write interfaces but not the compute interface. To bridge this gap, this work proposes a serverless computing-based cloud storage auditing system for existing mainstream cloud object storage. The proposed system leverages existing cloud storage auditing schemes as a basic building block and makes two adaptations. One is that we use the read interface of cloud object storage to support block data requests in a traditional cloud storage auditing scheme. Another is that we employ the serverless computing paradigm to support block data computation as traditionally required. Leveraging the characteristics of serverless computing, the proposed system realizes economical, pay-as-you-go cloud storage auditing. The proposed system also supports mainstream cloud storage upper layer applications(e.g., file preview) by not modifying the data formats when embedding authentication tags for later auditing. We prototyped and open-sourced the proposed system to a mainstream cloud service, i.e., Tencent Cloud. Experimental results show that the proposed system is efficient and promising for practical use. For 40 GB of data, auditing takes approximately 98 s using serverless computation. The economic cost is 120.48 CNY per year, of which serverless computing only accounts for 46%. In contrast, no existing studies reported cloud storage auditing results for real-world cloud services.

关键词： cloud storage auditing serverless computing object storage usability

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Optical scattering imaging with sub-nanometer precision based on position-ultra-sensitive giant Lamb shift

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 96-105页

作者： Zeyang liao Yu-wei Lu wei Li Xue-Hua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen 518045China

The Lamb shift of a quantum emitter in close proximity to a plasmonic nanostructure can be three or more orders of magnitude larger than that in the free space and is ultra-sensitive to the emitter position and *** demonstrate that this large Lamb shift can be sensitively observed from the scattering or absorption spectrum dip shift of the coupled system when the plasmonic nanoparticle or tip scans the *** these observations,we propose a scanning optical scattering imaging method based on the plasmonic-enhanced Lamb shift with achieves sub-nanometer *** method is based on the scattering or absorption spectrum of the plasmon-emitter coupling system,which is free of the fluorescence quenching problem and easier to implement in a plasmon-emitter coupling *** addition,our scheme works even if the quantum emitter is slightly below the dielectric surface,which can bring about broader applications,such as detecting atoms and molecules or quantum dots above or under a surface.

关键词： Lamb shift plasmon optical scattering imaging

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A new and efficient method for the synthesis of isoquinoline-3-carboxylate

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Chinese Chemical Letters 2008年第3期19卷 253-255页

作者： xiang wei liao Bao He Guan Zhan Zhu Liu Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050. PR China

An isoquinoline-3-carboxylate compound 3 was obtained with a moderate yield of 40% when N-acetyl-（3′-hydroxy-4′- methoxy-5′-methyl）phenylalanine methyl ester 1 was refluxed in HMTA/TFA. However, the anticipated product N-acetyl-（3′- hydroxy-4′-methoxy-5′-methyl-6′-formyl）phenylalanine methyl ester 2 could not be found. The possible mechanism was discussed in this article.

关键词： Isoquinolinc-3-carboxylate Duff reaction N-Acetyl-phenylalanine methyl ester

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Comparative effectiveness of several adjuvant therapies after hepatectomy for hepatocellular carcinoma patients with microvascular invasion

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 554-570页

作者： Yin-Xuan Pei Chen-Guang Su Zheng liao wei-wei Li Zi-xiang Wang Jin-Long Liu Department of Hepatobiliary Surgery The Affiliated Hospital of Chengde Medical UniversityChengde 067000Hebei ProvinceChina

BACKGROUND For resectable hepatocellular carcinoma(HCC),radical hepatectomy is commonly used as a curative ***,postoperative recurrence significantly diminishes the overall survival(OS)of HCC patients,especially with microva-scular invasion(MVI)as an independent high-risk factor for *** some studies suggest that postoperative adjuvant therapy may decrease the risk of recurrence following liver resection in HCC patients,the specific role of adju-vant therapies in those with MVI remains *** To conduct a network meta-analysis(NMA)to evaluate the efficacy of various adjuvant therapies and determine the optimal adjuvant *** A systematic literature search was conducted on PubMed,EMBASE,and Web of Science until April 6,*** comparing different adjuvant therapies or comparing adjuvant therapy with hepatectomy alone were *** ratios(HRs)with 95%confidence intervals were used to combine data on recurrence free survival and OS in both pairwise meta-analyses and *** Fourteen eligible trials(2268 patients)reporting five different therapies were *** terms of reducing the risk of recurrence,radiotherapy(RT)[HR=0.34(0.23,0.5);surface under the cumulative ranking curve(SUCRA)=97.7%]was found to be the most effective adjuvant therapy,followed by hepatic artery infusion chemotherapy[HR=0.52(0.35,0.76);SUCRA=65.1%].Regarding OS improvement,RT[HR:0.35(0.2,0.61);SUCRA=93.1%]demonstrated the highest effectiveness,followed by sorafenib[HR=0.48(0.32,0.69);SUCRA=70.9%].INTRODUCTION Hepatocellular carcinoma(HCC)is the sixth most common malignant tumor in the world and ranks third in terms of worldwide malignant tumor mortality rates in 2020[1].Curative treatments for HCC include ablation,radical hepatectomy,and liver ***,ablation is suitable only for early-stage HCC patients,who represent a small percentage of the overall HCC *** liver transplantation serves as the optimal tre

关键词： Hepatocellular carcinoma Adjuvant therapy Network meta-analysis Transarterial chemoembolization Hepatic artery infusion chemotherapy Radiotherapy Sorafenib

Superconducting,Topological,and Transport Properties of Kagome Metals CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)

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Research 2024年第2期2023卷 753-762页

作者： Xin-wei Yi Zheng-wei liao Jing-Yang You Bo Gu Gang Su School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Faculty of ScienceNational University of Singapore117551Singapore Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum ComputationUniversity of Chinese Academy of SciencesBeijing 100190China

The recently discovered ATi_(3)Bi_(5)(A=Cs,Rb)exhibit intriguing quantum phenomena including superconductivity,electronic nematicity,and abundant topological ***_(3)Bi_(5)present promising platforms for studying kagome superconductivity,band topology,and charge orders in parallel with *** this work,we comprehensively analyze various properties of ATi_(3)Bi_(5)covering superconductivity under pressure and doping,band topology under pressure,thermal conductivity,heat capacity,electrical resistance,and spin Hall conductivity(SHC)using first-principles *** superconducting transition temperature(Tc)of CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)at ambient pressure are about 1.85 and 1.92 *** subject to pressure,Tc of CsTi_(3)Bi_(5)exhibits a special valley and dome shape,which arises from quasi-two-dimensional compression to three-dimensional isotropic compression within the context of an overall decreasing ***,Tc of RbTi_(3)Bi_(5)can be effectively enhanced up to 3.09 K by tuning the kagome van Hove singularities(VHSs)and flat band through *** can also induce abundant topological surface states at the Fermi energy(EF)and tune VHSs across ***,our transport calculations are in excellent agreement with recent experiments,confirming the absence of charge density ***,SHC of CsTi_(3)Bi_(5)can reach up to 226h·(e·Ω·cm)^(-1)at *** work provides a timely and detailed analysis of the rich physical properties for ATi_(3)Bi_(5),offering valuable insights for further experimental verifications and investigations in this field.

关键词： doping superconductivity conductivity

NFT Security Matrix:Towards Modeling NFT Ecosystem Threat

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3255-3285页

作者： Peng liao Chaoge Liu Jie Yin Zhi Wang xiang Cui Key Laboratory of Trustworthy Distributed Computing and Service Beijing University of Posts and TelecommunicationsBeijing100876China Zhongguancun Laboratory Beijing100094China Institute of Information Engineering Chinese Academy of SciencesBeijing100085China

Digital assets have boomed over the past few years with the emergence of Non-fungible Tokens(NFTs).To be specific,the total trading volume of digital assets reached an astounding$55.5 billion in ***,numerous security concerns have been raised by the rapid expansion of the NFT *** holders are exposed to a plethora of scams and traps,putting their digital assets at risk of being ***,academic research on NFT security is scarce,and the security issues have aroused rare *** this study,the NFT ecological process is comprehensively *** process falls into five different stages encompassing the entire lifecycle of ***,the security issues regarding the respective stage are elaborated and analyzed in depth.A matrix model is proposed as a novel contribution to the categorization of NFT security *** data are collected from social networks,the Ethereum blockchain,and NFT markets to substantiate our claims regarding the severity of security concerns in the NFT *** this comprehensive dataset,nine key NFT security issues are identified from the matrix model and then subjected to qualitative and quantitative *** study aims to shed light on the severity of NFT ecosystem security *** findings stress the need for increased attention and proactive measures to safeguard the NFT ecosystem.

关键词： Non-fungible token blockchain cyber security

Control method based on DRFNN sliding mode for multifunctional flexible multistate switch

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Global Energy Interconnection 2024年第2期7卷 190-205页

作者： Jianghua liao wei Gao Yan Yang Gengjie Yang College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108P.R.China Faculty of Automation Huaiyin Institute of Technology Huai’an 223003P.R.China

To address the low accuracy and stability when applying classical control theory in distribution networks with distributed generation,a control method involving flexible multistate switches(FMSs)is proposed in this *** approach is based on an improved double-loop recursive fuzzy neural network(DRFNN)sliding mode,which is intended to stably achieve multiterminal power interaction and adaptive arc suppression for single-phase ground ***,an improved DRFNN sliding mode control(SMC)method is proposed to overcome the chattering and transient overshoot inherent in the classical SMC and reduce the reliance on a precise mathematical model of the control *** improve the robustness of the system,an adaptive parameter-adjustment strategy for the DRFNN is designed,where its dynamic mapping capabilities are leveraged to improve the transient compensation ***,a quasi-continuous second-order sliding mode controller with a calculus-driven sliding mode surface is developed to improve the current monitoring accuracy and enhance the system *** stability of the proposed method and the convergence of the network parameters are verified using the Lyapunov theorem.A simulation model of the three-port FMS with its control system is constructed in MATLAB/*** simulation result confirms the feasibility and effectiveness of the proposed control strategy based on a comparative analysis.

关键词： Distribution networks Flexible multistate switch Grounding fault arc suppression Double-loop recursive fuzzy neural network Quasi-continuous second-order sliding mode

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